Unit 4
5 marks · NormalA market stall sells apples. On Monday, the price of a bag of apples is increased by 8%. At the end of the week, a graph is used to display the number of bags sold each day.
The price of a bag is $2.50 before the increase. Calculate the new price after the 8% increase.
Over the week, these numbers of bags are sold: 14, 17, 20, 13, 16, 11, 9.
Find the median and range of the number of bags sold per day.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) $2.70 dollars
(b) Median = 14; Range = 20 − 9 = 11
Common mistakes: adding percentage instead of multiplying by a factor; median found as an average of wrong values; incorrect range calculation
Show mark scheme and worked solution
Marking points
M1 (a) · 1 mark · Identifies multiplying factor (1.08) or correct method for percentage increase
A1 (a) · 1 mark · Arrives at $2.70 as final answer, correct to nearest cent (follow-through)
M2 (b) · 1 mark · Lists numbers in order or correctly identifies how to find median and range
A2 (b) · 1 mark · Correctly finds median (14) (follow-through)
A3 (b) · 1 mark · Correctly finds range (11) (follow-through)
Worked solution
a) New price = $2.50 × 1.08 = $2.70
b) Ordered list: 9, 11, 13, 14, 16, 17, 20
Median: The fourth value = 14
Range: 20 − 9 = 11