Question 644445
Let {{{ x }}} = the price of the article
Let {{{ p }}} = the profit when the article
is sold for Rs. 69
given:
{{{ 2p }}} = the profit when article is
sold for Rs. 78
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(1) {{{ 69 - x = p }}}
(2) {{{ 78 - x = 2p }}}
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Subtract (1) from (2)
(2) {{{ 78 - x = 2p }}}
(1) {{{ -69 + x = -p }}}
{{{ 9 = p }}}
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Substitute this result back into (1) or (2)
(1) {{{ 69 - x = 9 }}}
(1) {{{ x = 69 - 9 }}}
(1) {{{ x = 60 }}}
The cost price was Rs. 60
check:
(2) {{{ 78 - x = 2*9 }}}
(2) {{{ x = 78 - 18 }}}
(2) {{{ x = 60 }}}
OK