Fill in the blanks.
Alex spends
17 of his money on 2 pens and 2 marbles.
Each marble costs twice as much as each pen.
Let the price of 1 pen be 1 u.
- Cost of 1 marble = _____ 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 marble = 2 x 1 u = 2 u
(b)
Amount that Alex has spent
= 2 x 1 u + 2 x 2 u
= 2 u + 4 u
= 6 u
(c)
Fraction of the money he has left
= 1 -
17 =
67 17 of his money = 6 u
67 of his money = 6 x 6 u = 36 u
Amount that Alex has left = 36 u
(d)
Amount that Alex has at first
= 6 u + 36 u
= 42 u
Answer(s): (a) 2; (b) 6; (c) 36; (d) 42