Question 1148947
Question 1:


{{{(r+(r+5))*4=610}}}

{{{4(r+r+5)=610}}}
{{{4(2r+5)=610}}}
{{{2(2r+5)=305}}}
{{{4r+10=305}}}
{{{4r=295}}}
{{{r=73&3/4}}}
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Question 2:


x at 7%
15000-x at 5%

{{{0.07x+0.05(15000-x)=1005}}}

{{{0.07x+750-0.05x=1005}}}
{{{0.02x=1005-750}}}
{{{0.02x=255}}}
{{{x=12750}}}
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