[B].
[C].
[D].
Answer: Option C
Explanation:
3x – y = 27 = 33 x – y = 3 ….(i)
3x + y = 243 = 35 x + y = 5 ….(ii)
On solving (i) and (ii), we get x = 4.
If 3(x – y) = 27 and 3(x + y) = 243, then x is equal to: Read More »
Aptitude, Surds And Indices[B].
[C].
[D].
Answer: Option D
Explanation:
We know that 112 = 121.
Putting m = 11 and n = 2, we get:
(m – 1)n + 1 = (11 – 1)(2 + 1) = 103 = 1000.
If m and n are whole numbers such that mn = 121, the value of (m – 1)n + 1 is: Read More »
Aptitude, Surds And Indices[B].
[C].
[D].
Answer: Option C
Explanation:
xz = y2 10(0.48z) = 10(2 x 0.70) = 101.40
0.48z = 1.40
| z = | 140 | = | 35 | = 2.9 (approx.) |
| 48 | 12 |
Given that 100.48 = x, 100.70 = y and xz = y2, then the value of z is close to: Read More »
Aptitude, Surds And Indices[B].
[C].
[D].
Answer: Option A
Explanation:
5a = 3125 5a = 55
a = 5.
5(a – 3) = 5(5 – 3) = 52 = 25.
If 5a = 3125, then the value of 5(a – 3) is: Read More »
Aptitude, Surds And Indices[B].
[C].
[D].
Answer: Option B
Explanation:
Let (25)7.5 x (5)2.5 ÷ (125)1.5 = 5x.
| Then, | (52)7.5 x (5)2.5 | = 5x |
| (53)1.5 |
| 5(2 x 7.5) x 52.5 | = 5x | |
| 5(3 x 1.5) |
| 515 x 52.5 | = 5x | |
| 54.5 |
5x = 5(15 + 2.5 – 4.5)
5x = 513
x = 13.
(25)7.5 x (5)2.5 ÷ (125)1.5 = 5? Read More »
Aptitude, Surds And Indices[B].
[C].
[D].
Answer: Option D
Explanation:
Let (17)3.5 x (17)x = 178.
Then, (17)3.5 + x = 178.
3.5 + x = 8
x = (8 – 3.5)
x = 4.5
(17)3.5 x (17)? = 178 Read More »
Aptitude, Surds And Indices[B].
[C].
[D].
Answer: Option B
Explanation:
| (0.04)-1.5 = | 4 | -1.5 | ||
| 100 |
| = | 1 | -(3/2) | ||
| 25 |
= (25)(3/2)
= (52)(3/2)
= (5)2 x (3/2)
= 53
= 125.
[B].
[C].
[D].
Answer: Option A
Explanation:
(256)0.16 x (256)0.09 = (256)(0.16 + 0.09)
= (256)0.25
= (256)(25/100)
= (256)(1/4)
= (44)(1/4)
= 44(1/4)
= 41
= 4
(256)0.16 x (256)0.09 = ? Read More »
Aptitude, Surds And Indices[B].
[C].
[D].
Answer: Option B
Explanation:
| (10)150 ÷ (10)146 = | 10150 |
| 10146 |
= 10150 – 146
= 104
= 10000.
The value of [(10)150 ÷ (10)146] Read More »
Aptitude, Surds And Indices[B].
| 9 | 3 | % stock at 117 |
| 4 |
[C].
[D].
Answer: Option B
Explanation:
Let investment in each case be Rs. (143 x 117).
| Income in 1st case = Rs. | 11 | x 143 x 117 | = Rs. 1287. | ||
| 143 |
| Income in 2nd case = Rs. | 39 | x 143 x 117 | = Rs. 1394.25 | ||
| 4 x 117 |
| Clearly, 9 | 3 | % stock at 117 is better. |
| 4 |
Which is better investment: 11% stock at 143 or 9% stock at 117? Read More »
Aptitude, Stocks And Shares