Mathmetics
ISBT Mathmetics for all banking PO,Clerk,IBPS PO,Railway,SSC,IAS,OAS Exams
Q11. |
|
| 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 (13 + 23+ 33 + 43+ …….. + 103) - (13 + 23+ 33 + 43)
So, [(10 x 11)/2]2 - [(4x5)/2]2 = 3025 -100 = 2925
View AnswerQ12. |
|
| 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, x2 + y2 = 68 and ( x - y )2 = 36.
We know that, ( x - y )2 = x2 + y2 - 2xy
or 68 - 2xy = 36
or 2xy = 68+36 = 104
or xy = 104/2=52
View AnswerQ13. |
|
| 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 AnswerQ14. | Three-fourth of two-third of 240 is added to two-third 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
