Mathmetics
ISBT Mathmetics for all banking PO,Clerk,IBPS PO,Railway,SSC,IAS,OAS Exams
Q111. 

1)  1000  2)  1200 
3)  1400  4)  2000 
5)  None of these 
Answer : 1000
Explanation : Let, total numbers of students are x.
Explanation : Let, total numbers of students are x.
Girls = 3x/7. and boys = 1  3x/7 = 4x/7.
Below 10 years boys = (4x/7) 1/4 = 4x/28 = x/7
The girls are also below ten years of age = (3x/7) 5/6 = 5x/14
So, above ten years = x  (x/7 + 5x/14) = x x/2 = x/2
Given, x/2= 500
or x = 1000.
View Answer
Q112. 

1)  20 %  2)  24 % 
3)  25 %  4)  33.33 % 
5)  None of these 
Answer : 20 %
Explanation : Let, C.P of each article is Rs.1/.
Explanation : Let, C.P of each article is Rs.1/.
So, C.P of 20's articles = Rs.20/ and C.P of 4's articles = Rs.4/ i.e. profit
We know that, S.P = C.P + Profit = 20 + 4 = Rs. 24/
Therefore, % of profit = (4/20) x 100 = 20%
View Answer
Q113.  A vendor sells 20 articles and gets a profit which is equal to selling price of 4 articles. What is the percentage of profit in this transaction ? 
1)  20 %  2)  24 % 
3)  25 %  4)  33.33 % 
5)  None of these 
Answer : 25 %
Explanation : Let, S.P of each article is Rs.1/.
Explanation : Let, S.P of each article is Rs.1/.
So, S.P of 20's articles = Rs.20/ and S.P of 4's articles = Rs.4/ i.e. profit
We, know that C.P = S.P Profit = 20  4 = Rs. 16/
Therefore, % of profit = (4/16) x 100 = 25%
View Answer
Q114. 

1)  24  2)  36 
3)  48  4)  72 
5)  None of these 
Answer : 48
Explanation : Let, the number be x.
Explanation : Let, the number be x.
So,x48 = x/3
or xx/3= 48
or x = 72
Therefore, twothirds of 72 is 48.
View Answer
Q115. 

1)  30  2)  40 
3)  50  4)  60 
5)  None of these 
Answer : 60
Explanation : Given, A’s marks in Arithmetic is x and A’s marks in English y and x +y=150  (I)
Explanation : Given, A’s marks in Arithmetic is x and A’s marks in English y and x +y=150  (I)
so, x/3 = y/2
or 2x =3y
or 2x  3y = 0  (II)
Putting the value in both equation, we get y = 60.
View Answer
Q116. 

1)  2525  2)  2925 
3)  3025  4)  3225 
5)  None of these 
Answer : 3025
Explanation : We know that , the sum of the cube all natural number i.e. 1 n = [(n. n+1)/2]^{2}
Explanation : We know that , the sum of the cube all natural number i.e. 1 n = [(n. n+1)/2]^{2}
The sequence is (1^{3} + 2^{3}+ 3^{3} + 4^{3}+ …….. + 10^{3})
So, [(10 x 11)/2]^{2} = 3025
View Answer
Q117. 

1)  2295  2)  2425 
3)  2595  4)  2925 
5)  None of these 
Answer : 2925
Explanation : We know that , the sum of the cube all natural number i.e. 1 n = [(n. n+1)/2]^{2}
Explanation : We know that , the sum of the cube all natural number i.e. 1 n = [(n. n+1)/2]^{2}
The sequence is (1^{3} + 2^{3}+ 3^{3} + 4^{3}+ …….. + 10^{3})  (1^{3} + 2^{3}+ 3^{3} + 4^{3})
So, [(10 x 11)/2]^{2}  [(4x5)/2]^{2} = 3025 100 = 2925
View Answer
Q118. 

1)  16  2)  52 
3)  58  4)  104 
5)  None of these 
Answer : 52
Explanation : Let, two numbers are x and y respectively.
Explanation : Let, two numbers are x and y respectively.
So, x^{2} + y^{2} = 68 and ( x  y )^{2} = 36.
We know that, ( x  y )^{2 }= x^{2} + y^{2}  2xy^{ }
or 68  2xy = 36
or 2xy = 68+36 = 104
or xy = 104/2=52
View Answer
Q119. 

1)  2  2)  3 
3)  4  4)  5 
5)  None of these 
Answer : 3
Explanation : Let, the number be x.
Explanation : Let, the number be x.
2x + 20 = 8x  4
or 8x  2x = 20 + 4 = 24
or 6x =24
or x= 24/6= 4
View Answer
Q120.  Threefourth of twothird of 240 is added to twothird of a number, the resultant number is 360. What is value of the original number ? 
1)  180  2)  240 
3)  320  4)  360 
5)  None of these 
Answer : 360
Explanation : Given , 3/4 x 2/3 x 240 +2x/3 = 360
Explanation : Given , 3/4 x 2/3 x 240 +2x/3 = 360
or 120 + 2x/3 = 360
or x = 360
View Answer