Nelson had 1/3 as many green marbles as blue marbles. If he bought another 36 green marbles, the ratio of the remaining number of green marbles to blue marbles is 2:5. How many marbles does he have altogether?

3 answers

Nelson had 1/B as many green marbles as blue marbles.
G - B = 1/3 — 10
=> 3G - 3B = 1
If he bought another 36 green marbles, ratio of the remaining no : of green to blue marbles = 2:5
(G + 36)/B = 2/15 — (2)
5G + 180 = 2N.
5G - 2B = -180 — (2)
Solving (1) and (2)
(X2) 3G - 3B = 1
(X3) 5G -2B = -180
———————————————
-> 15G - 15B = 15
15G - 6B = - 540
———————-
9B = 555
B = 62
3G - 186 = 1
3G = 185
G = 62
Altogether there are = 124 marbles
X - green marbles at first

3X - blue marbles at first

(X+36)/3X = 2/5

X = 180 green marbles

180*3 = 540 blue marbles

180 + 540 = 720 marbles.
X = Y/3

X+36/Y = 2/5

Y = 540

X = 180

total 720 marbles initially

all together 720 + 36 = 756 finally