Find the reciprocal of \(\frac{\frac{2}{3}}{\frac{1}{2} + \frac{1}{3}}\)
\(\frac{4}{5}\)
\(\frac{5}{4}\)
\(\frac{2}{5}\)
\(\frac{6}{7}\)
Correct answer is B
\(\frac{2}{3}\) = \(\frac{2}{3}\)
= \(\frac{2}{3}\) x \(\frac{6}{5}\)
= \(\frac{4}{5}\)
reciprocal of \(\frac{4}{5}\) = \(\frac{1}{\frac{4}{5}}\)
= \(\frac{5}{4}\)
Find the smallest number by which 252 can be multiplied to obtain a perfect square
2
3
5
7
Correct answer is D
\(252 = 2^{2} \times 3^{2} \times 7\)
\(\therefore\) To make 252 a perfect square, the smalest number to multiply with = 7.
\(252 \times 7 = 1764 = 42^{2}\)
Divide the L.C.M of 48, 64, and 80 by their H.C.F
20
30
48
60
Correct answer is D
48 = 24 x 3, 64 = 26, 80 = 24 x 5
L.C.M = 26 x 3 x 5
H.C.F = 24
\(\frac{2^6 \times 3 \times 5}{2^4}\)
= 22 x 3 x 5
= 4 x 3 x 5
= 12 x 5
= 60
282
240
222
210
Correct answer is C
Let x represent Musa's total mark when he scores 57 in biology and Let Y represent Musa's total mark when he now scored 75 in biology, if he scored 75 in biology his new total mark will be \(\frac{Y}{4}\) = 60, y = 4 x 60 = 240
To get his total mark when he scored 57, subtract 57 from 75 to give 18, then subtract this 18 from the new total mark(ie. 240)
= 240 - 18
= 222
Evaluate (212)3 - (121)3 + (222)3
(313)3
(1000)3
(1020)3
(1222)3
Correct answer is C
Evaluate (212)3 - (121)3 + (222)3
(221)3+
(222)3
1211
121
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(1020)3