Important for :

1

E

Then CI of one and a half year= | [ | P | ( | 1 + | 8 | ) |
^{1} |
( | 1 + | 8 | ) |
^{1} |
– p | ] | ..........(i) | |

100 | 2×100 |

SI of one and a half year

= P × 3 × | 8 | ...........(ii) |

2×100 |

According to the question, CI – SI = 80

Equation (i) – equation (ii) = 80

By solving, P = 25000

Time = 3 years and Rate of interest = 8% per annum

Therefore SI = 25000 × 3 × | 8 | = Rs. 6000 |

100 |

Alternate method: CI of one and a half year

= 8 + 4 + 8 × | 4 | = 12.32% |

100 |

SI of one and a half year = 8 + 4 = 12%

According to the question, (12.32 – 12) % = 80

1% = 250

SI of 3 years = 8 × 4 = 24% = 250 × 24 = Rs. 6000

Hence, option E is correct.

2

B

Total work = 4 × 58 = 232 units (let the efficiency of one man is 1 unit)

Total work was done in the first 5 days

Total work was done in the first 5 days

= 5 × 4 = 20 units = | 80 | units |

4 |

Now 3 men and one woman will work in the next five days = efficiency of 3m + 1w

= 3 + | 1 | = | 13 |

4 | 4 |

Total work was done in the second 5 days

= 13 × | 5 | = | 65 | units |

4 | 4 |

Total work was done in the third 5 days = 2m + 2w

= 2 + | 1 | = 5 × | 5 | = | 25 | = | 50 | units |

2 | 2 | 2 | 4 |

Total work was done in the fourth 5 days = 1m + 3w

= 1 + | 3 | = | 7 | = 7 × | 5 | = | 35 | units |

4 | 4 | 4 | 4 |

After the fourth, 5 days only women will work therefore the total units of work done in the first four, five days = 20 days

= | 80 | + | 65 | + | 50 | + | 35 | = | 230 | units |

4 | 4 | 4 | 4 | 4 |

Remaining work = 232 – | 230 | = | 698 | = 174.5 units |

4 | 4 |

Efficiency of 4 women = 1 × | 4 | = 1 unit |

4 |

The number of days taken by 4 women to do 174.5 units = 174.5 days

Total number of days = 174.5 + 20 = 194.5 days

Hence, option B is correct.

3

E

Barun’s marks = 414 + 47 = 461

The sum of Anil’s and Barun's marks = 414 + 461 = 875

Chandan Marks = 48% of 875 = 420 = 52.5% of the total marks = 52.5% of x (let the total marks is x )

By solving, x = total marks = 800

Dinesh’s marks = 420 + 32 = 452

Reqd. % = | 452 × 100 | = 56.5% |

800 |

Hence, option E is correct.

4

D

The respective ratio of the present age of grandfather, father, mother and son is 25 : 14 : 11 : 6

The ratio of the present age of grandfather and son = 25 : 6

Let us assume it 25x and 6x

According to the question,

25x – 9 | = | 13 |

6x – 9 | 3 |

By solving, x = 30

The age of father + mother = 14x + 11x = 25x = 25 × 30 = 750

After 9 years, the sum of their age = 750 + 18 = 768 years

Average = | 768 | = 384 years |

2 |

Hence, option D is correct.

5

A

Let the length of the rectangle = 4 units

And breadth of the rectangle = 3 units

Then diagonal of the rectangle = √(4^{2} + 3^{2}) = 5 units

According to the question, the length of a rectangle is increased by 25% and the breadth is reduced by 33.33%

New length = 125% of 4 units = 5 units

New breadth = 66.66% of 3 units = 2 units

In the new rectangle, New diagonal= √(5^{2} + 2^{2}) = √29 = approximately 5.38 units

And breadth of the rectangle = 3 units

Then diagonal of the rectangle = √(4

According to the question, the length of a rectangle is increased by 25% and the breadth is reduced by 33.33%

New length = 125% of 4 units = 5 units

New breadth = 66.66% of 3 units = 2 units

In the new rectangle, New diagonal= √(5

Change = (5.38 – 5) × | 100 | = 7.6% |

5 |

Hence, option A is correct.