By what percentage did the shop's total notebook…

By what percentage did the shop's total notebook sales rise from May to July?

Question 10

MediumOriginal question

The table shows the number of notebooks a stationery shop in Pune sold in four months.

Month	Ruled	Unruled
April	240	160
May	200	120
June	300	150
July	280	120

By what percentage did the shop's total notebook sales rise from May to July?

25%Correct answerYour answer40%Correct answerYour answer80%Correct answerYour answer125%Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer A

Correct answer: A

May total: $200 + 120 = 320$ . July total: $280 + 120 = 400$ .
Rise: $400 - 320 = 80$ .
Percentage rise: $\frac{80}{320} \times 100 = 25\%$ .

Worth noting

40% is the rise in ruled notebooks alone. 125% is July's total as a percentage of May's, not the rise. 80% mistakes the rise of 80 notebooks for a percentage.

Concept: Percentage change of a row total
Typical timeTypical: 80 s
Your timeYours: —

The rule this testsTables

Practise this chapter →

Ten questions from Data Interpretation, at your own pace.

Practise this chapter →

Ten questions from Data Interpretation, at your own pace.

By what percentage did the shop's total notebook sales rise from May to July?

Question 10

Explanation