Question 373858
You need a common denominator {{{2*25=50}}}

{{{(8/25)(2/2)=16/50}}}
{{{(7/10)(5/5)=35/50}}}
{{{(3/5)(10/10)=30/50}}}
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{{{8/25-7/10-3/5=16/50-35/50-30/50}}}
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{{{8/25-7/10-3/5=(16-35-30)/50}}}
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{{{highlight(8/25-7/10-3/5=-49/50)}}}