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tmead84
what's 3/8+2/5?
you have to get the same denominator, so let's see what numbers 8 and 5 will both go into. 8*5=40 and i don't see a lower number they will both divide into. so to make 3/8 into ?/40 we have to multiply the top by the same as we needed to multiply the bottom to get 40. \[\frac{ 3*5 }{8*5 } = \frac{ 15 }{ 40}\] and \[\frac{ 2*8 }{8*5 } = \frac{ 16 }{ 40}\] so \[\frac{15 }{ 40 }+\frac{ 16 }{ 40 }=\frac{ 31 }{ 40 }\]
oh. so you have to get lcd for both. ok. thanks