PSLE
Oscar and John were paid a total of $2230 for a job they did. John was paid $1220 less than Oscar.

1. How much was John paid for the job?
2. Oscar and John were paid based on the number of days they worked. Oscar worked 3 times as many days as John. Oscar was paid $5 more than John per day. How many days did Oscar work? 

(a)
Amount that John was paid = 1 u
Amount that Oscar was paid = 1 u + 1220

Total amount paid
= 1 u + 1 u + 1220
= 2 u + 1220

2 u + 1220 = 2230
2 u = 2230 - 1220
2 u = 1010

1 u = 1010 ÷ 2 = 505

Amount that John was paid
= 1 u
= $505

(b)
Amount that Oscar was paid
= 1 u + 1220
= 505 + 1220
= $1725

Oscar worked 3 times as many days as John.

3 sets of Oscar's salary = $1725

1 set of Oscar's salary
= 1725 ÷ 3
= $575

1 set of John's salary = $505

Difference between each set of Oscar's and John's salaries
= 575 - 505
= $70

Number of days in 1 set
= 70 ÷ 5
= 14

Number of days that Oscar worked
= 3 x 14
= 42

Answer(s): (a) $505; (b) 42