Question 1106727
x, y, z, how many each of P20, P50, P100 bills
{{{system(x+y+z=90,3.5=y/x,1/2=z/x)}}}


Use the last two equations to rewrite the first equation all in one variable, x.


{{{system(y=3.5x,z=x/2)}}}

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{{{x+3.5x+x/2=90}}}------solve this for x.

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