Eric received $4 from his mother in the 1st week of school and $6 in the 2nd week. Each week, he receives $2 more than the week before.
- How much money did he received in the 12th week?
- In which week did he receive $30?
(a)
Amount that Eric received on 1st Week = $4
Amount that Eric received on 2nd Week = $11
Formula:
Amount received each week = 4 + (Week number - 1) x $2
Amount received on Week 12
= 4 + (12 - 1) x 2
= 4 + 11 x 2
= 4 + 22
= $26
(b)
Week number that Eric received $30
= [(30 - 4) ÷ 2] + 1
= (26 ÷ 2) + 1
= 13 + 1
= 14
Answer(s): (a) $26; (b) 14