Question 1043544
Let {{{ a }}} = number of messages sent by Latoya
Let {{{ b }}} = number of messages sent by Austin
Let {{{ c }}} = number of messages sent by Trey
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(1) {{{ a + b + c = 125 }}}
(2) {{{ a = b + 7 }}}
(3) {{{ c = 4a }}}
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(2) {{{ b = a - 7 }}}
Plug (2) and (3) into (1)
(1) {{{ a + a - 7 + 4a = 125 }}}
(1) {{{ 6a = 132 }}}
(1) {{{ a = 22 }}}
and
(2) {{{ b = 22 - 7 }}}
(2) {{{ b = 15 }}}
and
(3) {{{ c = 4*22 }}}
(3) {{{ c = 88 }}}
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The number of messages sent by Latoya is 22
The number of messages sent by Austin is 15
The number of messages sent by Trey is 88
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check:
(1) {{{ a + b + c = 125 }}}
(1) {{{ 22 + 15 + 88 = 125 }}}
(1) {{{ 125 = 125 }}}
OK