PSLE
Mr Chong used two printers with different printing rates for a printing job. He started Printer H at 19 02 and started Printer J two minutes later. He stopped both printers at 19 07. 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 H at the time Mr Chong started Printer J?
2. What was the difference in the number of pages printed by the two printers from 19 02 to 19 07?
3. Which printer, H or J, has a faster 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 19 04, number of pages that Printer H printed = 96

(b)
Number of pages printed by Printer H from 19 02 to 19 07
= 240

Number of pages printed by Printer J from 19 02 to 19 07
= 180

Difference in the number of pages printed by the two printers from 19 02 to 19 07
= 240 - 180
= 60

(c)
Printing rate of Printer H
= 240 ÷ 5
= 48

Printing rate of Printer J
= 180 ÷ 3
= 60 (Faster)

Difference in the number of pages printed by the printers in one minute
= 60 - 48
= 12

Answer(s): (a) 96; (b) 60; (c) J, 12