Fill in the blanks.
Abraham spends
110 of his money on 4 pens and 3 erasers.
Each eraser costs thrice as much as each pen.
Let the price of 1 pen be 1 u.
- Cost of 1 eraser = _____ 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 eraser = 3 x 1 u = 3 u
(b)
Amount that Abraham has spent
= 4 x 1 u + 3 x 3 u
= 4 u + 9 u
= 13 u
(c)
Fraction of the money he has left
= 1 -
110 =
910 110 of his money = 13 u
910 of his money = 9 x 13 u = 117 u
Amount that Abraham has left = 117 u
(d)
Amount that Abraham has at first
= 13 u + 117 u
= 130 u
Answer(s): (a) 3; (b) 13; (c) 117; (d) 130