PSLE
Ivan and Jack were paid a total of $2680 for a job they did. Jack was paid $920 less than Ivan.

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

(a)
Amount that Jack was paid = 1 u
Amount that Ivan was paid = 1 u + 920

Total amount paid
= 1 u + 1 u + 920
= 2 u + 920

2 u + 920 = 2680
2 u = 2680 - 920
2 u = 1760

1 u = 1760 ÷ 2 = 880

Amount that Jack was paid
= 1 u
= $880

(b)
Amount that Ivan was paid
= 1 u + 920
= 880 + 920
= $1800

Ivan worked 2 times as many days as Jack.

2 sets of Ivan's salary = $1800

1 set of Ivan's salary
= 1800 ÷ 2
= $900

1 set of Jack's salary = $880

Difference between each set of Ivan's and Jack's salaries
= 900 - 880
= $20

Number of days in 1 set
= 20 ÷ 4
= 5

Number of days that Ivan worked
= 2 x 5
= 10

Answer(s): (a) $880; (b) 10