Fill in the blanks.
Adam spends
15 of his money on 3 pencils and 5 erasers.
Each eraser costs four times as much as each pencil.
Let the price of 1 pencil be 1 u.
- Cost of 1 eraser = _____ u
- Amount that Adam has spent = _____ u
- Amount that Adam has left = _____ u
- Amount that Adam has at first = _____ u
(a)
Change X times into units.
Cost of 1 pencil = 1 u
Cost of 1 eraser = 4 x 1 u = 4 u
(b)
Amount that Adam has spent
= 3 x 1 u + 5 x 4 u
= 3 u + 20 u
= 23 u
(c)
Fraction of the money he has left
= 1 -
15 =
45 15 of his money = 23 u
45 of his money = 4 x 23 u = 92 u
Amount that Adam has left = 92 u
(d)
Amount that Adam has at first
= 23 u + 92 u
= 115 u
Answer(s): (a) 4; (b) 23; (c) 92; (d) 115