Alice spent some money on 60 stamps of two different values. The values of stamps could be 5-cents, 10-cents,20-cents and 30-cents. The total amount of money he spent was between $5 and $10. 2/5 of the tamps cost 4/3 times as much as the rest of the stamps.

Question

a)What were the two values of stamps that she spent her money on?
b)How many stamps of each value did she buy?
c) How much money did she spend altogether?

Answer 1

Let the number of stamps of 5 cents be x
Let the number of stamps of 10 cents be y
Let the number of stamps of 20 cents be z
then the number of stamps of 30 cents = 60
[2/5 of total stamps] * u = [(1 - 2/5) of Total stamps] 4/3v
u = 2v
Case 1
u = 10, v = 5
u[2/5 * 60] = 24u
24u = 24 * 10 = $2.40
; v [3/5 * 60] = 36v
36v = 36 * 5 = $1.80
Total amount = 240 + 180 = $4.20 = No
Case 2
u = 20, v = 10
u[2/5 * 60] = 24u ; v[3/5 * 60] = 365
24u = 24 * 20 = $4.80 ;
36v = 36 * 10 = $3.60
Total amount = $4.80 + 3.60 = $8.40
a) Hence, Value of the stamps was 10 cents and 20 cents
b) She bought 24 stamps of 20 cents and 36 stamps of 10 cents
c) Total money spent = $8.40