Let the income of first person be Rs. 9x and the income of second person be Rs. 7x. Again, let the expenditures of first and second person be 4y and 3y respectively. Then,
Saving of first person = 9x - 4y
Saving of second person = 7x - 3y
∴ 9x - 4y = 200 ...(i)
and 7x - 3y = 200 ...(ii)
From (i), we have
9x - 4y = 200
Substituting the value of x in (ii), we have
Substituting the value of y in (iii), we get
Hence, monthly income of First person
= Rs. 9x = Rs. (9 × 200) = Rs. 1800
and monthly income of second person
= Rs. 7x = Rs. (7 × 200) = Rs. 1400.
Problems Based on Elimination Method
Solve the following system of equations by elimination method
6(ax + by) = 3a + 2b
6(bx - ay) =3b - 2a.
A motor boat whose speed is 24 km/h in still water takes 1 hour more to go 32km upstream than to return downstream to the same spot. Find the speed of the stream.
If the points A(k + 1, 2k), B(3k, 2k + 3) and C(5k – 1, 5k) are collinear, then find the value of k.