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6.	By what least number 675 be multiplied to obtain a number which is a perfect cube?
	A.  5
	B.  6
	C.  7
	D.  8

Solution

675 = 5 x 5 x 3 x 3 x 3 To make it a perfect cube, it must be multiplied by 5.

7.	Find the smallest number by which 5808 should be multiplied so that the product becomes a perfect square?
	A.  2
	B.  3
	C.  7
	D.  11

Solution

5808 = 2 x 2 x 2 x 2 x 3 x 11 x 11 = 22 x 22 x 3 x 112. To make it a perfect square, it must be multiplied by 3.

8.	√.081 ×.484 / .0064 ×6.25 is equal to
	A.  0.9
	B.  0.99
	C.  9
	D.  99

Solution

Sum of decimal places in the numberator and denominator under the radical sign being the same, we remove the decimal. Given exp. = √ 81 ×484 / 64 ×625 = 9 × 22 / 8 ×25 = 0.99.

9.	If a = 0.1039, then the value of √4a2 - 4a + 1 + 3a is
	A.  0.1039
	B.  0.2078
	C.  1.1039
	D.  2.1039

Solution

√4a2 - 4a + 1 + 3a = √(1)2 + (2a)2 - 2 ×1 ×2a + 3a ‹=›√(1 - 2a)2 + 3a ‹=› (1 - 2a) + 3a ‹=› (1 + a) ‹=› (1 + 0.1039) = 1.1039.

10.	√50 × √98 is equal to
	A.  63.75
	B.  65.95
	C.  70
	D.  70.25

Solution

√50 × √98 = √ 50 ×98 ‹=› √4900 70.