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Question
Solve for x and y:
0.4x + 0.3y = 1.7, 0.7x – 0.2y = 0.8.
Solution
The given system of equations is
0.4x + 0.3y = 1.7 …….(i)
0.7x – 0.2y = 0.8 …….(ii)
Multiplying (i) by 0.2 and (ii) by 0.3 and adding them, we get
0.8x + 2.1x = 3.4 + 2.4
⇒2.9x = 5.8
⇒x = `(5.8)/(2.9)` = 2
Now, substituting x = 2 in (i), we have
0.4 × 2 + 0.3y = 1.7
⇒0.3y = 1.7 – 0.8
⇒y = `(0.9)/(0.3)` = 3
Hence, x = 2 and y = 3.
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