Fill in the blanks.
Alex spends
14 of his money on 3 pens and 5 coins.
Each coin costs thrice as much as each pen.
Let the price of 1 pen be 1 u.
- Cost of 1 coin = _____ u
- Amount that Alex has spent = _____ u
- Amount that Alex has left = _____ u
- Amount that Alex has at first = _____ u
(a)
Change X times into units.
Cost of 1 pen = 1 u
Cost of 1 coin = 3 x 1 u = 3 u
(b)
Amount that Alex has spent
= 3 x 1 u + 5 x 3 u
= 3 u + 15 u
= 18 u
(c)
Fraction of the money he has left
= 1 -
14 =
34 14 of his money = 18 u
34 of his money = 3 x 18 u = 54 u
Amount that Alex has left = 54 u
(d)
Amount that Alex has at first
= 18 u + 54 u
= 72 u
Answer(s): (a) 3; (b) 18; (c) 54; (d) 72