document.write( "Question 1025424: 26,876 is invested, part at 9% and the rest at 5%. If the interest earned from the amount invested at 9% exceeds the interest earned from the amount invested at 5% by 720.78, how much is invested at each rate? \n" ); document.write( "

Algebra.Com's Answer #640662 by mananth(16946) $\"\"$ $\"About$

You can put this solution on YOUR website!
Part I 9.00% per annum ------------- x
\n" ); document.write( "Part II 5.00% per annum ------------ y
\n" ); document.write( " total investment 26876
\n" ); document.write( " Interest----- from greater part = 9.00% x
\n" ); document.write( " Interest from smaller part= 5.00% y
\n" ); document.write( " greater by 720.78
\n" ); document.write( " 9.00% x = 5.00% y + 720.78
\n" ); document.write( " multiply by 100
\n" ); document.write( " 9 x - -5 y = 72078 --------1
\n" ); document.write( "x + y = 26876 -------- 2
\n" ); document.write( "eliminate y
\n" ); document.write( "Multiply 1 by 1
\n" ); document.write( "Multiply 2 by 5
\n" ); document.write( "we get
\n" ); document.write( "9 x - -5 y = 72078
\n" ); document.write( "5 x - 5 y = 134380
\n" ); document.write( "14 x = 206458
\n" ); document.write( "/ 14
\n" ); document.write( " x= 14747
\n" ); document.write( "Plug the value of x in in 1
\n" ); document.write( "132723 -5 y = 72078
\n" ); document.write( " -5 y = 72078 -132723
\n" ); document.write( " -5 y = -60645
\n" ); document.write( " / -5
\n" ); document.write( " y= 12129
\n" ); document.write( "$ 14747 at 9.00%
\n" ); document.write( "$ 12129 at 5.00%
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "720.78 = 1327.23 - 606.45
\n" ); document.write( " \n" ); document.write( "

\n" );