Hey, everyone! If youโre getting ready for your 11+ exams or helping your child prepare, youโll want every trick in the book to make the most of your time during the test. Today, letโs dig deep into a typical 11+ maths problem and learn how to use estimation to blast through tricky questionsโespecially when youโre running out of time.
Grab a snack and settle in, because this blog is jam-packed with practical tips, step-by-step calculations, and loads of visuals: everything you need to master estimation for the 11+.
Table of Contents
- Introduction: Why Estimation Matters
- The Sample Problem
- Initial Thoughts: Spotting Estimation Opportunities
- Step-by-Step: Estimating the Pocket Money
- Crunching the Paper Round Earnings
- Combining Your Estimates
- Shortcuts for Multiple Choice Questions
- Why Estimation Saves You Time
- Tips for Developing an โEstimation Mindsetโ
- Practising with Real 11+ Problems
- Common Mistakes & How to Avoid Them
- Final Thoughts: Exam Day Strategy
- Join the Conversation!
Introduction: Why Estimation Matters
Itโs no secret: timing is everything in the 11+ exam! As you edge closer to the end of the paper, that clock starts ticking faster and panic might set in. You spot a question with heaps of numbers and think, โThis could take ages!โ But what if you didnโt have to get the answer to the exact penny?
Estimation is your secret weapon. It lets you:
- Quickly narrow down your choices,
- Avoid silly mistakes,
- And squeeze out those precious last marksโmaybe even the one needed for your place at grammar school!
โYou donโt have to be so precise, because if you look at the answersโฆ thereโs quite a big difference between them, right?โ
You might have heard a teacher say something similar. If not, youโre reading it now!
The Sample Problem
Letโs start with the exact question from our transcript:
โSammy gets ยฃ15 pocket money each month from his parents. He also gets ยฃ9.50 each week from his paper round. How much money does Sammy get in one year?โ
Thereโs a reason questions like these pop up near the end of 11+ maths papersโthey make you juggle monthly and weekly calculations, and if youโre short on time, itโs easy to get stuck.
Hereโs how weโll attack it, step by step.
Initial Thoughts: Spotting Estimation Opportunities
First, when you see a question like this, donโt panic. Instead, look at the possible answers (if itโs multiple choice). The transcript gave these options:
- ยฃ60
- ยฃ674
- ยฃ1,656
- ยฃ849
- ยฃ1,347
- ยฃ249
Whoa! Thatโs a massive spread, isnโt it? You donโt need the exact answer to know that ยฃ60 is way too low and ยฃ1,656 is likely too high. This is your first clue: estimation is not just allowed, itโs essential.
Quick tip: If the options have big gaps between them, donโt waste time trying to be perfect.
Step-by-Step: Estimating the Pocket Money
Letโs break down the pocket money calculationโmonthly earnings.
Sammy gets ยฃ15 each month.
How much does that add up to in one year? Well, there are 12 months in a year.
Letโs work this out:
ยฃ15 ร 12 = ?
You could grab your calculator, but we want to save time.
Fast Mental Calculation
Split 12 into 10 and 2:
- 15 ร 10 = ยฃ150
- 15 ร 2 = ยฃ30
- Add them: ยฃ150 + ยฃ30 = ยฃ180
So, from just the pocket money, Sammy gets ยฃ180 per year.
(Visual: Stack of coins or a 12-month calendar with ยฃ15 marked each month)
Crunching the Paper Round Earnings
The question also says Sammy gets ยฃ9.50 each week from his paper round.
There are 52 weeks in a year, so in theory:
ยฃ9.50 ร 52 = ?
Method 1: Going Through the Full Calculation
Splitting ยฃ9.50 into ยฃ9 and ยฃ0.50 (50p):
- ยฃ9 ร 52 = ยฃ468
- ยฃ0.50 ร 52 = ยฃ26
- Total = ยฃ468 + ยฃ26 = ยฃ494
But wait! In an exam, full calculations like this can eat up your time. Is there a smarter way?
Method 2: Estimation for Speed
Is ยฃ9.50 close to a round number? YES! Itโs nearly ยฃ10.
Think of it as ยฃ10 ร 52 = ยฃ520.
Butโฆ Since ยฃ9.50 is 50p less than ยฃ10, every week Sammy gets 50p less than ยฃ10.
Total difference over 52 weeks:
- 0.50 ร 52 = ยฃ26
So, from the over-estimate:
- ยฃ520 (if he got ยฃ10 each week)
- Subtract ยฃ26 (the โoverestimateโ)
So, real total for the year: ยฃ494 (same as above).
โNine pound fifty is very close to ten pounds. And so ten times fifty-two is five hundred and twenty.โ
Key estimation tip: Round to the nearest simple number, then adjust at the end if needed!
Combining Your Estimates
Right, now letโs add Sammyโs two sources of incomeโfor the full year.
- Pocket money: ยฃ180
- Paper round: ยฃ494 (if you calculated exactly) or roughly ยฃ520 (if you estimate high)
Letโs do both, so you get comfortable with estimation and then checking your answer.
Estimate First
- ยฃ180 (pocket money)
- ยฃ520 (paper round, estimated high)
Total: ยฃ180 + ยฃ520 = ยฃ700 (estimated upper limit)
But wait, we know ยฃ520 is a bit too high because we rounded up.
Accurate Calculation
- ยฃ180 + ยฃ494 = ยฃ674
So a precise total (doing the full calculation) is ยฃ674.
(Visual: Two bar charts side by side โ estimation vs actual, to illustrate the difference)
Shortcuts for Multiple Choice Questions
Letโs remember those answer choices:
- ยฃ60
- ยฃ674
- ยฃ1,656
- ยฃ849
- ยฃ1,347
- ยฃ249
If you have a smart estimate of around ยฃ700, only ยฃ674 makes sense. All the other options are way offโeither much too high or much too low.
โโฆthe only feasible answer in a very short space of time is going to be 674. I know that because I’ve said my answer be less than 700. It’s only two possible answers less than 700. One of them is way less. And obviously that’s not going to be an appropriate answer.โ
See how estimating first helps you eliminate wrong answers fast?
Why Estimation Saves You Time
Letโs put yourself in the shoes of the exam.
With just a few minutes to go, do you want to spend your time multiplying decimals and double-checking every penny, or do you want to collect as many marks as possible?
Hereโs why estimation is so powerful:
- It acts as a sense-check: Stops silly mistakes (like miscounting months or weeks)
- It helps eliminate impossible options in multiple choice
- It frees up time for really tricky problems where you do need exact answers
When to Use Estimation
- When numbers are round or close to round
- When options are spread far apart
- When youโre running out of time
- When you just need to rule things out
Pro tip: โNot like crazy estimations, just sense of estimation so that my answer can be, you know, taken very quickly and I don’t have to go through every single process and I don’t have to be so accurate that it takes a lot of my timeโฆโ
Tips for Developing an โEstimation Mindsetโ
Itโs not just about this questionโitโs about making estimation second nature. Hereโs how you can train your brain to estimate quickly and effectively:
1. Practise Rounding Up and Down
- If a number is ยฃ9.50, think โIs this closer to ยฃ10, or ยฃ9?โ
- Sometimes rounding up gives a safer estimateโso long as you remember itโs an OVER-estimate.
2. Break Big Multiplications into Easier Pieces
- e.g., For 15 ร 12, split 12 into 10 + 2:
- 15 ร 10 = 150
- 15 ร 2 = 30
- Total: 150 + 30 = 180
3. Use โFriendly Numbersโ
- Think in 10s, 50s, 100s. Theyโre easier and quicker to work with in your head.
4. Quickly Sense-Check
- If your estimate is way higher or lower than any answer, double-checkโdid you round in the wrong direction?
5. Eliminate the Impossible
- If you know the total has to be more than ยฃ200, cross out ยฃ60 and ยฃ249 straight away.
- If you know it can’t possibly be over ยฃ1,000, cross out those numbers too.
Practising with Real 11+ Problems
Letโs try a few other similar estimation challenges, so you cement the skills. Adapt these for your own revision or with your child!
Example 1: Weekly and Daily Allowance
Jamie gets ยฃ10 every week and ยฃ2 every day during school holidays (14 weeks/year). How much does Jamie get in a year?
Estimate:
- ยฃ10/week x 52 weeks = ยฃ520
- ยฃ2/day x 7 days/week x 14 weeks = ยฃ2 x 98 = ยฃ196
Total: ยฃ520 (round to ยฃ500 if youโre rushing)
Add ยฃ200 (from ยฃ2/day during holidays)
Final estimate: About ยฃ700
Example 2: Saving With Estimation
A board game costs ยฃ13.45. If you want to buy five, about how much will it cost?
- ยฃ13 ร 5 = ยฃ65 (if you round down)
- ยฃ15 ร 5 = ยฃ75 (if you round up)
The answer will be between ยฃ65 and ยฃ75โprobably closest to ยฃ67-ish.
Common Mistakes & How to Avoid Them
Even the best students slip up now and then. Here are the top estimation mistakes and how you can dodge them:
Mistake 1: Not Rounding Correctly
Not sure if you should round up or down? Ask yourself: do I want to be sure my answer isnโt too high or too low? For test questions, itโs usually okay to round up when in doubt, as long as you adjust at the end.
Mistake 2: Forgetting to Adjust
If you round ยฃ9.50 up to ยฃ10, remember to fix that at the end by subtracting the extra you โaddedโ.
Mistake 3: Not Checking the Big Picture
If you work out that the answer is ยฃ1,234 but the biggest option is ยฃ500, you need to look again!
Mistake 4: Panicking and Freezing
Remember, sometimes good enough is good enough. Especially at the end of a test, itโs better to estimate and pick the best answer than leave it blank.
Final Thoughts: Exam Day Strategy
Exams are as much about technique as they are about maths knowledge. Smart estimation gives you those crucial marks when time is against you.
โSo hopefully this has helped youโฆ exam technique is so important.โ
Remember, the 11+ isnโt just about working things out perfectlyโitโs about doing your best under pressure. Use estimation as a tool and not a crutch. Practise it at home, so come exam day, itโs second nature.
Quick Checklist for Using Estimation in the Exam
- [ ] Check if the answers are widely spaced (then estimate!)
- [ ] Look for friendly numbers to round to
- [ ] Use addition, subtraction, and multiplication tricks to make sums super quick
- [ ] Sense-check your answer against what should be reasonable
- [ ] Move on quickly to the next question if youโre happy with your estimate
(Visual: Quick estimation checklist, e.g. exam desk with a clock and maths paper)
Join the Conversation!
If this blog post helped you, let us know! Drop a comment below sharing your top estimation tip or a question youโd like answered in a future post.
If youโre prepping for the 11+ and want more advice, resources, or just a bit of encouragement, reach out! Weโre always happy to help make your prep as smooth and successful as possible.
โIf you still needed some help, please get in contact and we would love to support your child.โ
Best of luck with your studies. Rememberโyou can do this! And smart estimation might be just the ticket to your top score.
Take care, and see you in the next blog!
(Visual: Smiling student with a stack of books marked โ11+ Practiceโ)
Resources for Extra Practice
Share Your Thoughts!
Have questions or tips about estimation? Share them in the comments below, or contact us directly.
And if you found this useful, donโt forget to like and shareโmore students should have the confidence to estimate and succeed!
โNot like crazy estimations, just sense of estimation so that my answer can be, you know, taken very quickly and I don’t have to go through every single processโฆโ
Youโre one step closer to beating the 11+ maths with confidence!

