Answer: 10
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Work Shown:
x/25 = 2/5
5x = 25*2
5x = 50
x = 50/5
x = 10
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Another approach:
x/25 = 2/5
x/25 = (2*5)/(5*5)
x/25 = 10/25
x = 10
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Yet another method:
x/25 = 2/5
x/25 = 0.4
x = 25*0.4
x = 10