Fill in the blanks.
Adam spends
12 of his money on 4 buttons and 2 erasers.
Each eraser costs thrice as much as each button.
Let the price of 1 button 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 button = 1 u
Cost of 1 eraser = 3 x 1 u = 3 u
(b)
Amount that Adam has spent
= 4 x 1 u + 2 x 3 u
= 4 u + 6 u
= 10 u
(c)
Fraction of the money he has left
= 1 -
12 =
12 12 of his money = 10 u
12 of his money = 1 x 10 u = 10 u
Amount that Adam has left = 10 u
(d)
Amount that Adam has at first
= 10 u + 10 u
= 20 u
Answer(s): (a) 3; (b) 10; (c) 10; (d) 20