Emma thinks of a number, adds 7, and gets 15. What number did Emma think of?
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Let Emma's number be x. So x + 7 = 15. To find x, subtract 7 from both sides: x = 15 - 7 = 8. Emma thought of 8. ✓
Algebra accounts for roughly 3 to 6 questions on a typical GL 11+ maths paper, around 6 to 12 percent, but its true reach is wider because sequences, missing-number problems, and function machines all rely on algebraic thinking without being labelled "algebra". (GL does not publish official topic weightings, so these figures are careful estimates from practice-paper analysis, flagged here for honesty.)
For many parents, "algebra" sounds advanced for a ten-year-old. In the 11+ it is gentler than it sounds: substituting a value into an expression, solving a simple equation, following a number machine, or continuing a sequence. Every question is multiple choice with five options, and a child who understands the idea can usually reach the answer in under a minute.
The biggest barrier is rarely the maths itself. It is the idea that a letter stands for a number, and that the equals sign means "both sides balance", not "the answer is". Get those two ideas secure and 11+ algebra becomes very approachable.
Every question is multiple choice with five options (A to E), spanning D1 to D3. Based on practice-paper analysis (GL publishes no official weightings, so treat the order as indicative), GL tests:
These map directly onto the Year 6 curriculum: using simple formulae, generating linear sequences, expressing missing-number problems with letters, and finding pairs of numbers that satisfy an equation with two unknowns. D3 questions occasionally stretch into early Year 7 territory.
Five questions drawn from PrepStep’s algebra bank, spanning Foundation to Challenging. Tap “Show worked explanation” to see the full method after you’ve had a go. The correct answer is highlighted on each question so you can check immediately.
Emma thinks of a number, adds 7, and gets 15. What number did Emma think of?
Let Emma's number be x. So x + 7 = 15. To find x, subtract 7 from both sides: x = 15 - 7 = 8. Emma thought of 8. ✓
Jack is j years old. His sister Sophie is 3 years younger. Which expression shows Sophie's age?
If Jack is j years old and Sophie is 3 years younger, then Sophie's age = j - 3. ✓
A number machine multiplies by 3 then adds 2. If you put 5 into the machine, what comes out?
Input = 5. First multiply by 3: 5 × 3 = 15. Then add 2: 15 + 2 = 17. Output = 17. ✓
Lily thinks of a number, multiplies it by 4, then adds 5 to get 29. What was Lily's number?
Let the number be x. So 4x + 5 = 29. First subtract 5: 4x = 24. Then divide by 4: x = 6. Lily's number was 6. ✓
Lucy is n years old. Her mum is 28 years older. In 5 years' time, how old will Lucy's mum be?
Lucy's mum is now n + 28. In 5 years she'll be (n + 28) + 5 = n + 33 years old. ✓
Common mistake 1 of 4
Misreading the equals sign.
Tip: Many children think "=" means "write the answer". In 8 + 4 = __ + 5 the answer is 7, not 12. Both sides must weigh the same.
Common mistake 2 of 4
Reading "3a" as "3 and a".
Tip: The hidden multiplication sign trips children up; 3a means 3 times a. When substituting a = 5, that is 15, not 8 and not 35.
Common mistake 3 of 4
Reversing a number machine in the wrong order.
Tip: To undo "times 3 then add 5", subtract 5 first, then divide by 3. List the steps and reverse them bottom to top.
Common mistake 4 of 4
Translating words backwards.
Tip: "5 less than a number" is n minus 5, not 5 minus n. GL deliberately offers both, so slow, careful translation matters more than speed here.
Yes, though lightly. Practice-paper analysis suggests roughly 3 to 6 algebra questions per paper, covering substitution, simple equations, function machines, and sequences. Many other "number" questions also use algebraic thinking, so the reasoning shows up more often than the raw count implies.
Year 6 level algebra: substituting a value into an expression, solving one-step and two-step equations, following number machines forwards and backwards, continuing sequences, and simple "think of a number" problems. It does not require advanced techniques, just secure understanding of letters as numbers.
Usually less hard than parents expect. The maths is gentle; the real hurdles are conceptual, mainly understanding that a letter represents a number and that the equals sign means "balance". Once those click, most children handle 11+ algebra confidently.
Treating the equals sign as "the answer goes here" rather than as a balance, and misreading "3a" as "3 and a" instead of "3 times a". GL builds wrong answers directly around these two misconceptions.
Start with missing-number problems (7 + ? = 12) before introducing letters, use a balance-scale picture for equations, and practise function machines both forwards and backwards. Building from arithmetic they already understand removes most of the anxiety around the word "algebra".
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