Peter spent $540 on a guitar.He spent 1/7 of his remaining money on a watch.He still had 3/8 of his money left.How much money had he at first?
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Let x be the money he had before he bought items
(x - 540)/7 + 3x/8 + 540 = x
LCD = 56
8(x - 540) + 21x + 540*56 = 56x
8x - 4320 + 21x + 30240 = 56x
27x = 25920
x = 960
He had $960 at first.
(x - 540)/7 + 3x/8 + 540 = x
LCD = 56
8(x - 540) + 21x + 540*56 = 56x
8x - 4320 + 21x + 30240 = 56x
27x = 25920
x = 960
He had $960 at first.
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(x - 540) - (1/7)(x - 540) = (3/8)x
(6/7)(x - 540) = (3/8)x
48(x - 540) = 21x
48x - (48)(540) = 21x
27x = (48)(540)
x = (48)(20) = 960
He started with $960.
check:
Peter spent $540 on a guitar 960 - 540 = 420
He spent 1/7 of his remaining money on a watch. 420 - 60 = 360
He still had 3/8 of his money left 3/8 of 960 is 360
(6/7)(x - 540) = (3/8)x
48(x - 540) = 21x
48x - (48)(540) = 21x
27x = (48)(540)
x = (48)(20) = 960
He started with $960.
check:
Peter spent $540 on a guitar 960 - 540 = 420
He spent 1/7 of his remaining money on a watch. 420 - 60 = 360
He still had 3/8 of his money left 3/8 of 960 is 360