PSLE
Justin and Ian were paid a total of $3960 for a job they did. Ian was paid $1720 less than Justin.

1. How much was Ian paid for the job?
2. Justin and Ian were paid based on the number of days they worked. Justin worked 2 times as many days as Ian. Justin was paid $25 more than Ian per day. How many days did Justin work? 

(a)
Amount that Ian was paid = 1 u
Amount that Justin was paid = 1 u + 1720

Total amount paid
= 1 u + 1 u + 1720
= 2 u + 1720

2 u + 1720 = 3960
2 u = 3960 - 1720
2 u = 2240

1 u = 2240 ÷ 2 = 1120

Amount that Ian was paid
= 1 u
= $1120

(b)
Amount that Justin was paid
= 1 u + 1720
= 1120 + 1720
= $2840

Justin worked 2 times as many days as Ian.

2 sets of Justin's salary = $2840

1 set of Justin's salary
= 2840 ÷ 2
= $1420

1 set of Ian's salary = $1120

Difference between each set of Justin's and Ian's salaries
= 1420 - 1120
= $300

Number of days in 1 set
= 300 ÷ 25
= 12

Number of days that Justin worked
= 2 x 12
= 24

Answer(s): (a) $1120; (b) 24