Question 1013078
Let {{{ a }}} = number of cups of ice cream sold
Let {{{ b }}} = number of cones sold
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(1) {{{ .6a + 2b = 200 }}}
(1) {{{ 6a + 20b = 2000 }}}
(1) {{{ 3a + 10b = 1000 }}}
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You need another equation to actually solve this.
You have 2 unknowns and only 1 equation
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{{{ a }}} has to be a multiple of {{{ 10 }}}, since
that's the only way to end up with {{{ 0 }}} in the
units digit of {{{ 200 }}}
So, there are many possible answers:
{{{ 3*10 + 10b = 1000 }}}
{{{ 3*20 + 10b = 1000 }}}
{{{ 3*30 + 10b = 1000 }}}
etc.
Find {{{ b }}} for each equation
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But the problem is still that you are missing data