The ration of A and B's monthly salary is 5 : 6, their expenses is 3 : 4 and his savings are Rs. 1800 and Rs. 1600, then what is his monthly salary of B?
Answers
Ratio of their salary A: B = 5 : 6
Let x be the constant ratio
Ratio of their salary A: B = 5x : 6x
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Ratio of their expenses : A : B = 3 : 4
Let y be the constant ratio:
Ratio of their expenses : A : B = 3y : 4y
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Form the equations and solve for x and y:
3y + 1800 = 5x ---------------- [ 1 ]
4y + 1600 = 6x ---------------- [ 2 ]
[ 1 ] x 4 : 12y + 7200 = 20x -------------- [ 3 ]
[ 2 ] x 3 : 12y + 4800 = 18x -------------- [ 4 ]
[ 3 ] - [ 4 ] :
2400 = 2x
x = 1200 -------------- [ sub into [ 1 ] ]
3y + 1800 = 5(1200)
3y = 6000 - 1800
3y = 4200
y = 1400
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Find B's salary:
B's salary = 6x = 6(1200) = Rs 7200
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Answer: B's salary is Rs 7200
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