Question 550035
The pipes are assumed to fill tank at different rates
Let {{{r[1]}}} = rate for pipe 1
Let {{{r[2]}}} = rate for pipe 2
Let {{{r[3]}}} = rate for pipe 3
Let {{{r[4]}}} = rate for pipe 4
-----------------------
given:
(1) {{{ r[1] + r[2] + r[3] = 1/12 }}}
(2) {{{ r[2] + r[3] + r[4] = 1/15 }}}
(3) {{{ r[1] + r[2] = 1/20 }}}
------------------
Substitute (3) into (1)
(1) {{{ 1/20 + r[3] = 1/12 }}}
(1) {{{ r[3] = 1/12 - 1/20 }}}
(1) {{{ r[3] = 5/60 - 3/60 }}}
(1) {{{ r[3] = 1/30 }}}
-----------------
This is 4 unknowns and only 3 equations.
Is some data missing?
I don't think this can be solved