IF 217X + 131Y = 913, 131X + 217Y = 827, THEN X + Y Is

If 217x + 131y = 913, 131x + 217y = 827, then x + y is

(a) 5

(b) 6

(c) 7

(d) 8

(a) 5

Explanation:

Given equations are:

217x + 131y = 913 ----------(i)

131x + 217y = 827 ----------(ii)

Now, (i) + (ii)

= (217x + 131y) + (131x + 217y) = 913 + 827

= (217x + 131x) + (131y + 217y) = 1740

= 348x + 348y = 1740

= 348 (x + y) = 1740

= x + y = `frac{348}{1740}`

= x + y = 5

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CBSE Class 10 Mathematics Sample Paper-2022