PSLE
Ken and Archie were paid a total of $1740 for a job they did. Ken was paid $1140 more than Archie.

1. How much was Archie paid for the job?
2. Ken and Archie were paid based on the number of days they worked. Ken worked 4 times as many days as Archie. Archie was paid $20 less than Ken per day. How many days did Ken work? 

(a)
Amount that Archie was paid = 1 u
Amount that Ken was paid = 1 u + 1140

Total amount paid
= 1 u + 1 u + 1140
= 2 u + 1140

2 u + 1140 = 1740
2 u = 1740 - 1140
2 u = 600

1 u = 600 ÷ 2 = 300

Amount that Archie was paid
= 1 u
= $300

(b)
Amount that Ken was paid
= 1 u + 1140
= 300 + 1140
= $1440

Ken worked 4 times as many days as Archie.

4 sets of Ken's salary = $1440

1 set of Ken's salary
= 1440 ÷ 4
= $360

1 set of Archie's salary = $300

Difference between each set of Ken's and Archie's salaries
= 360 - 300
= $60

Number of days in 1 set
= 60 ÷ 20
= 3

Number of days that Ken worked
= 4 x 3
= 12

Answer(s): (a) $300; (b) 12