Fill in the blanks.
Abraham spends
18 of his money on 3 pens and 3 coins.
Each coin costs four times as much as each pen.
Let the price of 1 pen be 1 u.
- Cost of 1 coin = _____ u
- Amount that Abraham has spent = _____ u
- Amount that Abraham has left = _____ u
- Amount that Abraham has at first = _____ u
(a)
Change X times into units.
Cost of 1 pen = 1 u
Cost of 1 coin = 4 x 1 u = 4 u
(b)
Amount that Abraham has spent
= 3 x 1 u + 3 x 4 u
= 3 u + 12 u
= 15 u
(c)
Fraction of the money he has left
= 1 -
18 =
78 18 of his money = 15 u
78 of his money = 7 x 15 u = 105 u
Amount that Abraham has left = 105 u
(d)
Amount that Abraham has at first
= 15 u + 105 u
= 120 u
Answer(s): (a) 4; (b) 15; (c) 105; (d) 120