# Quantitative Aptitude Part-5[For Railway-SSC-Bank]

QUANTITATIVE APTITUDE#5
1.188.88 + 8.88 + 288.8 + 888.8 - 40.888 = ?
a)1334.472
b)1346.465
c)1372.477
d)1378.469
e)1349.455

2.The ratio of milk to water is 4:3 in a mixture of 490 litres. To make this ratio 4:5 the quantity of water to be further added should be
a)115 litres
b)140 litres
c)143 litres
d)165 litres
e)90 litres

3.In how many different ways can the letters of the word 'MUMBAI' be arranged?
a)520
b)340
c)120
d)360
e)748

4.The average weight of seven members of a family is 18kg. If the head of the family is not considered, the average weight of other members becomes less by 6kg. The weight of the head of the family is:
a)50kg
b)54kg
c)44kg
d)34kg
e)30kg

5.A is twice as good a workman as B. Together, they finish the work in 14 days. In how many days can it be done by each of them separately?
a)19,38
b)20,40
c)21,42
d)21,22
e)18,36

6.Rs.7000 was borrowed from a bank by Damu at a simple interest. He paid Rs.3000 after 3 years and Rs.5450 at the end of 5 years from the date of borrowing to the bank to settle the account. Find the rate of interest.
a)5.67%
b)3.33%
c)2.45%
d)4.14%
e)6.99%

7.There is a rectangular field. The length of the field is three times its breadth. Rs.750 is required to paint the floor at the rate of Rs.10 per square metre, then the length of the field is?
a)15 metres
b)16 metres
c)14 metres
d)20 metres
e)22 metres

Directions(8-10): What should come in place of (?) in the following number series?

8. 50    60    72    ?    103.68    124.416
a)83
b)85.5
c)90.74
d)86.4
e)82.7

9. 10    ?    30    75    225    787.5    3150
a)11
b)13
c)15
d)17
e)19

10. 20    ?    100    300    1050    4200    18900
a)40
b)60
c)55
d)70
e)35

1.a)
2.b)
3.d)
4.b)
5.c)
6.d)
7.a)
8.d)
9.c)
10.a)
Solution
1.? = 188.88 + 8.88 + 288.8 + 888.8  ̶  40.888 = 1334.472

2.Total quantity of mixture = 490 litres
Ratio of milk to water = 4:3
Let milk be 4x litres and water be 3x litres
Then, 4x + 3x = 490
Or, x = 70
So, Milk = 70×4 = 280 litres and Water = 70×3 = 210 litres
Let y litres of water be added.
Then, 280/(210+y) = 4/5
Or, y = 140 litres

3.Given word MUMBAI
So, there are six letters, in which ‘M’ appears twice.
So, required no. of ways = 6! ÷ 2! = 3 × 4 × 5 × 6 = 360

4.Total weight of seven members of the family = 18 × 7 = 126kg
Total weight of the family without its head = (18   ̶  6) × 6 = 72kg
Weight of the head of the family = (126 ̶ 72) = 54kg

5.Given that A is twice as good a workman as B.
If the work done by B in 1 day is 1/x, then that by A is 2/x
According to the question,
14[(1/x) + (2/x)] = 1
Or, 14[(1 + 2)/x] = 1
Or, x = 42
So, B can do this work in 42 days and A can do the work in 42/2 = 21 days

6.Principal = Rs.7000
Amount = Rs.(3000+5450) = Rs.8450
Interest = (Amount ̶ Principal) = Rs.(8450  ̶  7000) = Rs.1450
Time = 5 years
So, rate = (Interest × 100) / (Time × Pricipal)
= (1450 × 100) / (5 × 7000)
= 4.14%

7.Let the length of the field be 3x and breadth be x metres.
Area of the field = Total cost of painting ÷ Painting cost per sq. metre
= 750/10 = 75 sq.m
According to the question,
3x × x = 75
Or, x = 5
So, Length of the field = (5 × 3)m
= 15 metres

8.The series is:   50
50 × 1.2 = 60;
60 × 1.2 = 72;
72 × 1.2 = 86.4;
86.4 × 1.2 = 103.68;
103.68 × 1.2 = 124.416;

9.The series is:   10
10 × 1.5 = 15;
15 × 2.0 = 30;
30 × 2.5 = 75;
75 × 3.0 = 225;
225 × 3.5 = 787.5;
787.5 × 4.0 = 3150;

10.The series is: 20
20 × 2 = 40;
40 × 2.5 = 100;
100 × 3.0 = 300;
300 × 3.5 = 1050;
1050 × 4.0 = 4200…… 