PSLE
Ian and Archie were paid a total of $1580 for a job they did. Archie was paid $1280 less than Ian.

1. How much was Archie paid for the job?
2. Ian and Archie were paid based on the number of days they worked. Ian worked 5 times as many days as Archie. Ian was paid $8 more than Archie per day. How many days did Ian work? 

(a)
Amount that Archie was paid = 1 u
Amount that Ian was paid = 1 u + 1280

Total amount paid
= 1 u + 1 u + 1280
= 2 u + 1280

2 u + 1280 = 1580
2 u = 1580 - 1280
2 u = 300

1 u = 300 ÷ 2 = 150

Amount that Archie was paid
= 1 u
= $150

(b)
Amount that Ian was paid
= 1 u + 1280
= 150 + 1280
= $1430

Ian worked 5 times as many days as Archie.

5 sets of Ian's salary = $1430

1 set of Ian's salary
= 1430 ÷ 5
= $286

1 set of Archie's salary = $150

Difference between each set of Ian's and Archie's salaries
= 286 - 150
= $136

Number of days in 1 set
= 136 ÷ 8
= 17

Number of days that Ian worked
= 5 x 17
= 85

Answer(s): (a) $150; (b) 85