<PRE><B>Question 751866</B>
x = 5c: y = 10c

x  + y   = 50.......1
5x + 10y = 420......2

Multiply (1) by 10

10x + 10y = 500.....3
5x  + 10y = 420.....2

Subtract 2 from 3

5x        = 80
 x        = 16

Substitute x = 16 into Eqn (1)

16  +  y  =  50
       y  =  50 - 16
       y  =  34

Therefore there are 16 x 5c and 34 x 10c

Hope this helps.
:-)</PRE>