Explanation:Given:√x = 28
Squaring both sides:
x = 28² = 784
Now, √(25x / 49)
= √(25 × 784 / 49)
Since 784 ÷ 49 = 16,
= √(25 × 16)
= √400
= 20
So, the correct answer is 20.
112) Which of the following is NOT twin primes?
క్రింది వానిలో కవల ప్రధాన సంఖ్యలు కానివి ఏవి?
A) 41, 43
B) 29, 31
C) 87,89
D) 101, 103
View Answer
C) 87,89
Explanation:Twin primes are two prime numbers whose difference is 2.
Checking the given pairs:
41, 43 → both primes ✔
29, 31 → both primes ✔
87, 89 → 87 is not a prime ❌
101, 103 → both primes ✔
So, the pair which is NOT twin primes is 87, 89.
113) Write the following numbers in ascending order
క్రింది సంఖ్యలను ఆరోహణ క్రమంలో రాయండి
9.0901, 9.9001, 9.0991, 0.9991, 9.9991
A) 0.9991, 9.0991, 9.0901, 9.9001, 9.9991
B) 0.9991, 9.0901, 9.0991, 9.9001, 9.9991
C) 9.9991, 9.0901, 9.0991, 9.9001, 0.9991
D) 9.9001, 0.9991, 9.0901, 9.0991, 9.9991
View Answer
B) 0.9991, 9.0901, 9.0991, 9.9001, 9.9991
Explanation:Given numbers:
9.0901, 9.9001, 9.0991, 0.9991, 9.9991
Arranging in ascending order:
0.9991
9.0901
9.0991
9.9001
9.9991
This matches option 2.
114) =
A) 502400
B) 98596
C) 522400
D) 198596
View Answer
A) 502400
Explanation:Using the identity:
a² − b² = (a − b)(a + b)
Given: 957² − 643²
= (957 − 643)(957 + 643)
= 314 × 1600
= 502400
, then 
=