<PRE><B>Question 760998</B>
10 quarters and 12 dimes =
 {{{ 10*25 + 12*10 = 250 + 120 }}}
{{{ 250 + 120 = 370 }}}
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9 quarters and 13 dimes =
{{{ 9*25 + 13*10 = 225 + 130 }}}
{{{ 225 + 130 = 355 }}}
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8 quarters and 14 dimes =
{{{ 8*25 + 14*10 = 200 + 140 }}}
{{{ 200 + 140 = 340 }}}
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He has 8 quarters and 14 dimes
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also, you can say:
Let {{{ d }}} = number of dimes he has
Let {{{ q }}} = number of quarters he has
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(1) {{{ d + q = 22 }}}
(2) {{{ 10d + 25q = 340 }}} ( in cents )
Multiply both sides of (1) by {{{ 10 }}}
and subtract (1) from (2)
(2) {{{ 10d + 25q = 340 }}}
(1) {{{ -10d - 10q = -220 }}}
{{{ 15q = 120 }}}
{{{ q = 8 }}}
and
(1) {{{ d + q = 22 }}}
(1) {{{ d = 14 }}}
Same answer
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