Question 74679
{{{A = P + Prt}}}Plug in A=652, p =400 and r= 0.07
{{{652-400 = cross(400-400) + 400(0.07)t}}}Subtract 400 from both sides and evaluate 400*0.07
{{{252 = 28t}}}Divide both sides by 28
{{{252/28 = cross(28/28)t}}}
{{{t=9}}}
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Check:
{{{652 = 400 + 400(0.07)(9)}}}
{{{652 = 400 + 252}}}
{{{652 = 652}}}works