Question

A coin purse contain 5c,10c and 25c coins. The number of 10c is 3times as many 5c coins is two more than the 10c , If the Total Value of each contens is 490 pesos, How many each kind of coins are there in purse

Answer 1

Let +a+ = number of 5 c coins

Let +b+ = number of 10 c coins

Let +c+ = number of 25 c coins

given:

(1) 5a+10b+25c+= 490

(2) b = 3a

(3) c= b+2

Substitute (2) and (3) into (1)

(1) 5 x (b/3) + 10b + 25 x (b+2) = 490

(1) 5 x (b/3) + 10b + 25b + 50 = 490

(1) (5/3) x b + 35b = 440

Multiply both side by 3

(1) 5b + 105b = 1320

(1) 110b = 1320

(1) b = 12

(2) a = b/3

(2) a = 12/3

(2) a = 4

and

(3) c = b+2

(3) c = 12 + 2

(3)  c = 14

There are 4 of the 5 c coins

There are 12 of the 10 c coins

There are 14 of the 25 c coins