### Mathmetics

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

## Q11. | ## If 2 |

1) | 3:2 | 2) | 2:3 |

3) | 3:1 and 1:2 | 4) | 5:6 |

5) | None of these |

**Answer : 3:1 and 1:2**

**Explanation :**Given, 2

*x*

^{2 }-7

*xy +*3

*y*

^{2 }= 0

or 2(x/y)

^{2}-7(x/y)+ 3 = 0So,

*x/y*=3/1 and*x/y*=1/2**View Answer**

## Q12. | ## If |

1) | + only | 2) | - only |

3) | + or - | 4) | Can't be said |

5) | None of these |

**Answer : - only**

**View Answer**

## Q13. | ## If |

1) | x2+2x+8=0 | 2) | x2-4x+8=0 |

3) | x2-24x+128=0 | 4) | 2x2+8x+9=0 |

5) | None of these |

**Answer : x2-24x+128=0**

**Explanation :**Given,

*a+b*=24 and

*a-b*= 8

So,solving from two equations,we get

*a*=16 and*b*=8Therefore,

*ab*=16 x 8 = 128Quadratic equations

*x*

^{2}- ( sum of roots)

*x*+ products of the roots = 0

or

*x*^{2}-24*x*+128 = 0**View Answer**

## Q14. | ## What is the value of 'P' , if the following equation has two equal roots ?^{2} - (P-2)x + 1 = 0 |

1) | P=6 or P=-2 | 2) | P=4 or P=-3 |

3) | P=6 or P=-3 | 4) | P=4 or P=2 |

5) | None of these |

**Answer : P=6 or P=-2**

**Explanation :**Here, a=4,b= - (P-2); c=1

Given, equation has equal roots,then D=0

b

^{2}- 4ac =0or p

^{2}+4 - 4p - 16 = 0or p

^{2}- 6p +2p - 12 =0or p(p-6) + 2(p-2) = 0

or p=6 or -2

**View Answer**

## Q15. | ## A tank has leak which would empty the completely filled tank in 10 hours.If the tank is full of water and a tap is opened which admits 4 liters of water per minute in the tank, the leak takes 15 hours to empty the tank. How many liters of water does the tank hold ? |

1) | 2400 | 2) | 3600 |

3) | 4800 | 4) | 7200 |

5) | None of these |

**Answer : 7200**

**Explanation :**Let, the capacity of the tank be "X" liters.

According to the problem: 15 x (X/10 - 4 x 60) = X

Or X = 7200 liters

**View Answer**

## Q16. | ## The batting average of 30 innings of a cricketer is 40 runs. His highest score exceeds his lowest score by 100 runs.If these two innings are not included, the average of the remaining 28 innings is 38. What is the lowest score of the player ? |

1) | 12 | 2) | 16 |

3) | 18 | 4) | 20 |

5) | None of these |

**Answer : 18**

**Explanation :**Let, the highest and lowest score are x and y respectively.

So, x + y = (40 X 30 ) - (28 X 38) = 136 -------- (i)

Given, x-y = 100 -------- (ii)

Given, x-y = 100

By solving, the above equation we get, x= 118 and x = 18

**View Answer**

## Q17. | ## A vendor buy Fresh Fruits, contain 70% water and also buy Dry Fruits which contain 40% water. If he buys 120 kg of Fresh Fruits,how much quantity of Dry Fruits can be obtains from that quantity? |

1) | 56 kg | 2) | 60 kg |

3) | 64 kg | 4) | 72 kg |

5) | None of these |

**Answer : 60 kg**

**Explanation :**Given ,total quantity of fresh fruits = 120 kg

In the fresh fruits , water contain = 120 x (70/100 ) = 84 kg and non-water contain = 120-84 = 36 kg.

In the Dry fruits, water contain = 40% and non-water contain 60%.

Since, Non-water quantity is always constant i.e.

60% = 36 kg

or 100% = (36/60) x 100 = 60 kg

Thus , Dry fruits quantity = 60 kg in 120 kg of Fresh fruits .

**View Answer**

## Q18. | ## A shopkeeper marks up his goods by 50%. However, he could sell only one-third of his stock at this price. The half of the remaining stock was sold at a discount of 7.14% and remaining at a discount of 16.67%. What is the overall percentage profit of the trader ? |

1) | 28% | 2) | 32% |

3) | 36% | 4) | 38% |

5) | None of these |

**Answer : 38%**

**View Answer**

## Q19. | ## If |

1) | 16 | 2) | 18 |

3) | 20 | 4) | 22 |

5) | None of these |

**Answer : 22**

**Explanation :**

**First Method::**

We know that, 2ab = (a^{2} + b^{2}) - (a - b)^{2} = 125 - 81 = 44 or ab = 22.

**Second Method: **

We know that, (a - b)^{2} = a^{2} + b^{2} -2ab = 125- 2ab or 81 = 125 -2ab or 2ab = 125-81 =44

or ab =44/2=22

**View Answer**

## Q20. | ## A watch which gains uniformly is 2 minutes low at noon on Monday and is 4 min. 48 sec fast at 2 p.m. on the following Monday. When was it correct ? |

1) | 2 p.m. on Tuesday | 2) | 1 p.m. on Friday |

3) | 3 p.m. on Thursday | 4) | 2 p.m. on Wednesday |

5) | None of these |

**Answer : 2 p.m. on Wednesday**

**View Answer**