Stage 9 - Q1 - 2 marks
Multiply \(x\) by 4, then add 10. Write an expression.
Hint
Multiplication comes before the final addition.
Stage 9 - Q2 - 2 marks
Add 10 to \(x\), then multiply the result by 5.
Hint
The phrase “the result” refers to the whole previous expression.
Stage 9 - Q3 - 3 marks
Subtract the square of \(x\) from 15.
Hint
The square is being subtracted from the constant.
Stage 9 - Q4 - 3 marks
Subtract 12 from \(x\), then divide the result by 9.
Hint
A fraction bar groups the numerator.
Stage 9 - Q5 - 4 marks
A workshop charges USD 12 per booking plus USD 3 per item. Write the total cost C for \(x\) items.
Hint
Separate the fixed charge from the repeated charge.
Stage 9 - Q6 - 4 marks
A workshop charges USD 13 per booking plus USD 5 per item. Write the total cost C for \(x\) items.
Hint
Separate the fixed charge from the repeated charge.
Stage 9 - Q7 - 5 marks
Explain in words how to evaluate this expression.
Hint
Read the innermost bracket before the outer operation.
Stage 9 - Q8 - 5 marks
Find the constant difference A minus B.
Hint
Use brackets when subtracting the second expression.
Stage 9 - Q9 - 5 marks
A learner says “square \(x\), then add 3” and “add 3 to \(x\), then square” always give the same result. Test \(x=0\) and decide.
Hint
One counterexample disproves an “always” claim.
Stage 9 - Q10 - 3 marks
Machine A triples an input then adds 8. Machine B adds a fixed number b then triples the result. Find b so the outputs agree for every input. Can b be an integer?
Hint
The \(x\) terms already match.