Question 1109979
Plot {{{ C }}}, total cost on vertical axis
Plot {{{ t }}} = time in days on the horizontal
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Renting the machine:
(1) {{{ C = ( 25 + 5 )*t }}}
(2) {{{ C = 7t + 650 }}}
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I'll find out when the costs are equal
{{{ ( 25 + 5 )*t = 7t + 650 }}}
{{{ 30t = 7t + 650 }}}
{{{ 23t = 650 }}}
{{{ t = 28.261 }}}
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The Rental costs become greater during the 28th day
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check:
I'll say {{{ t = 28.265 }}}
(1) {{{ C = 30*28.265 }}}
(1) {{{ C = 847.95 }}}
and
(2) {{{ C = 7*28.265 + 650 }}}
(2) {{{ C = 197.855 + 650 }}}
(2) {{{ C = 847.855 }}}
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Ok -the rental costs become slightly higher on day 28