Simplification

1:If 2 tables and 3 chairs cost Rs. 3500 and 3 tables and 2 chairs cost Rs. 4000, then how much does a table cost ? A)500 B)1000 C)1500 D)2000 Answer : Option B Explanation: Let the cost of a table and that of a chair be Rs. x and Rs. y respectively. Then, 2x + 3y = 3500 ...(i) and 3x + 2y = 4000 .....(ii) solving (i) and (ii) we get x = 1000, y = 500 2:If a - b = 3,a2+b2=29,find the value of ab. A)10 B)12 C)15 D)18 Answer : Option A Explanation: 2ab=(a2+b2)-(a-b)2=29-9=20ab=10 3:If a = 1 - x and b = 2x + 1, then for what value of x, a is equal to b ? A)1 B)-1 C)-2 D)0 Answer : Option d Explanation: x = y =>1 - q = 2q + 1 =>3q = 0 =>q = 0. 4: (41)2+(38)2× (0.15)sup>2 = ? A)3125.0225 B)1713.49 C)3125.15 D)59204.0225 Answer : Option B Explanation: (41)2+(38)2× (0.15)2 = ? 1681 + 1444 × 0.0225 1681 + 32.49 = 1713.49 5: 2 + [2 + {2 + (2 + (2 + 23)}] = ? A)17/4 B)33/4 C)65/4 D)129/4 E)Non of these Answer : Option B Explanation: 2 + [2 + {2 + (2 + (2 + 23)}] = 2 + 6 + 1/4 = 33/4

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