Fill in the blanks.
Adam spends
19 of his money on 3 erasers and 3 beads.
Each bead costs twice as much as each eraser.
Let the price of 1 eraser be 1 u.
- Cost of 1 bead = _____ 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 eraser = 1 u
Cost of 1 bead = 2 x 1 u = 2 u
(b)
Amount that Adam has spent
= 3 x 1 u + 3 x 2 u
= 3 u + 6 u
= 9 u
(c)
Fraction of the money he has left
= 1 -
19 =
89 19 of his money = 9 u
89 of his money = 8 x 9 u = 72 u
Amount that Adam has left = 72 u
(d)
Amount that Adam has at first
= 9 u + 72 u
= 81 u
Answer(s): (a) 2; (b) 9; (c) 72; (d) 81