Question: 31 -
Which natural number is nearest to 8485, which is completely divisible by 75 ?
-
8500
-
8475
-
8550
-
8525
Answer:
8475
Solution:
On dividing we get
75)8485(113
75
------
98
75
------
235
225
------
10
------
Required number = (8485-10)=8475.
On dividing we get
75)8485(113
75
------
98
75
------
235
225
------
10
------
Required number = (8485-10)=8475.
Question: 32 -
How many terms are in the G.P. 3, 6, 12, 24, ......., 384 ?
-
10
-
11
-
9
-
8
Answer:
8
Solution:
Here a = 3 and r = 6/3 = 2. Let the number of terms be n.
Then, t = 384 => a * r^(n-1) = 384
=> 3 * 2^(n-1) = 384 => 2^(n-1) = 128 = 2^(7)
=> n-1 = 7 => n = 8.
Here a = 3 and r = 6/3 = 2. Let the number of terms be n.
Then, t = 384 => a * r^(n-1) = 384
=> 3 * 2^(n-1) = 384 => 2^(n-1) = 128 = 2^(7)
=> n-1 = 7 => n = 8.
Question: 33 -
On dividing 2272 as well as 875 by 3-digit number N,we get the same remainder. The sum of the digits of N is:
-
13
-
10
-
11
-
12
Answer:
10
Solution:
(2272-875) = 1397, is exactly divisible by N.
Now , 1397 = 11 x 127
The required 3-digit number is 127
the sum of digits is 10.
(2272-875) = 1397, is exactly divisible by N.
Now , 1397 = 11 x 127
The required 3-digit number is 127
the sum of digits is 10.
Question: 34 -
Which one of the following cannot be the square of a natural number?
-
81225
-
20164
-
32761
-
42437
Answer:
42437
Solution:
The square of a natural number never ends in 7.
42437 is not the square of a natural number
The square of a natural number never ends in 7.
42437 is not the square of a natural number
Question: 35 -
If 60% of 3/5 of a number is 36, then the number is
-
115
-
94
-
86
-
100
Answer:
100
Solution:
Let the number be x.Then
=> 60% of 3/5of x=36.
=> (60/100*3/5*)x=36
=> 9x/25=36 => x=25*36/9=100
Required number is 100.
Let the number be x.Then
=> 60% of 3/5of x=36.
=> (60/100*3/5*)x=36
=> 9x/25=36 => x=25*36/9=100
Required number is 100.