Joel had 3/10 as much money as Abel. Abel gave $85 to Joel. As a result Joel now has twice as much as Abel. How much had they altogether?
+118667 Joel had 3/10 as much money as Abel. Abel gave $85 to Joel. As a result Joel now has twice as much as Abel. How much had they altogether?
J=0.3A (1)
J+85 = 2( A-85) (2)
find J+A
Sub (1) into (2)
0.3A+85=2(A-85)
0.3A+85=2A-170
0.3A+85+170=2A-170+170
0.3A+255=2A
0.3A+255-0.3A=2A-0.3A
255=1.7A
A=$150
J=0.3*150 = $45
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so altogether they have 150+45 = $195
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0.3*150=45 good
150-85=65 45+85=130 65*2=130 great :)
A's money =x Joels money = 3/10x A's money AFTER he gave away 85 = x-85
J = 2 (x-85) after the 'trade'
The TOTAL money in the system does not change.....Before=after
x + 3/10x = (x-85) + 2(x-85)
13/10 x = 3x - 255
17/10 x = 255
x= 255 * 10/17 = 150 So J had 3/10 x 150 = 45 150 +45 = 195
