PSLE
Mark and Zeph were paid a total of $4120 for a job they did. Mark was paid $1640 more than Zeph.

1. How much was Zeph paid for the job?
2. Mark and Zeph were paid based on the number of days they worked. Mark worked 2 times as many days as Zeph. Zeph was paid $10 less than Mark per day. How many days did Mark work? 

(a)
Amount that Zeph was paid = 1 u
Amount that Mark was paid = 1 u + 1640

Total amount paid
= 1 u + 1 u + 1640
= 2 u + 1640

2 u + 1640 = 4120
2 u = 4120 - 1640
2 u = 2480

1 u = 2480 ÷ 2 = 1240

Amount that Zeph was paid
= 1 u
= $1240

(b)
Amount that Mark was paid
= 1 u + 1640
= 1240 + 1640
= $2880

Mark worked 2 times as many days as Zeph.

2 sets of Mark's salary = $2880

1 set of Mark's salary
= 2880 ÷ 2
= $1440

1 set of Zeph's salary = $1240

Difference between each set of Mark's and Zeph's salaries
= 1440 - 1240
= $200

Number of days in 1 set
= 200 ÷ 10
= 20

Number of days that Mark worked
= 2 x 20
= 40

Answer(s): (a) $1240; (b) 40