Question 44136
3/5+1/2+3/4=t
where "t" is the time she spent exercising
multiply both sides by all the denominators:
3(2*4)+1(5*4)+3(5*3)=(5*2*4)t
24+20+75=40t
t=(24+20+75)/40
t=2.975 hours

I hope this helps 
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