PSLE
Mr Gan used two printers with different printing rates for a printing job. He started Printer R at 14 29 and started Printer S one minute later. He stopped both printers at 14 34. The graphs show the total number of pages printed by each printer from the start of printing.

1. How many pages had been printed by Printer R at the time Mr Gan started Printer S?
2. What was the difference in the number of pages printed by the two printers from 14 29 to 14 34?
3. Which printer, R or S, has a slower printing rate? What is the difference in the number of pages printed by the printers in one minute? Give your answer in this format. (Eg A, 1)

(a)
At 14 30, number of pages that Printer R printed = 18

(b)
Number of pages printed by Printer R from 14 29 to 14 34
= 90

Number of pages printed by Printer S from 14 29 to 14 34
= 390

Difference in the number of pages printed by the two printers from 14 29 to 14 34
= 390 - 90
= 300

(c)
Printing rate of Printer R
= 90 ÷ 5
= 18 (Slower)

Printing rate of Printer S
= 390 ÷ 4
= 97.5 (Faster)

Difference in the number of pages printed by the printers in one minute
= 97.5 - 18
= 79.5

Answer(s): (a) 18; (b) 300; (c) R, 79.5