Question 149202
Let "x" = P 0.25
"y" = P 1.00
We know we have 20 coins in total, so {{{x+y=20}}} right? -----> eqn 1
Also, 0.25x + 1.00y = P 10.25 -------> eqn 2
In eqn 1, we get {{{y=20-x}}} and substitute it in eqn 2,
Continuing,
0.25x + 1.00(20-x) =10.25
0.25x + 20 - 1x = 10.25
re-arranging, 20-10.25 = x-0.25x 
0.75x = 9.75
{{{x=13}}} ------------> no. of P 0.25 coins
In eqn 1, {{{13 + y =20}}}, {{{y=7}}} -----> no. of P1.00
In doubt? Go back eqn 2,
(0.25*13) + (1*7) = 10.25 
3.25 + 7 = 10.25
P10.25=P10.25
<font><font size=4><b>Thank you,
Jojo</font>