Question: 21 -
Two numbers are respectively 20% and 50% more than a third number. The ratio of the two numbers is:
-
6:7
-
3 : 5
-
2 : 5
-
4 : 5
Answer:
4 : 5
Solution:
Let the third number be x.
Then, first number = 120% of x =
120x
=
6x
100
5
Second number = 150% of x =
150x
=
3x
100
2
Ratio of first two numbers =
6x
:
3x
= 12x : 15x = 4 : 5.
5
2
Let the third number be x.
Then, first number = 120% of x = | 120x | = | 6x |
100 | 5 |
Second number = 150% of x = | 150x | = | 3x |
100 | 2 |
Ratio of first two numbers = | 6x | : | 3x | = 12x : 15x = 4 : 5. | ||
5 | 2 |
Question: 22 -
A sum of money is to be distributed among A, B, C, D in the proportion of 5 : 2 : 4 : 3. If C gets Rs. 1000 more than D, what is B's share?
-
Rs. 1500
-
Rs. 500
-
None of these
-
Rs. 2000
Answer:
Rs. 2000
Solution:
Let the shares of A, B, C and D be Rs. 5x, Rs. 2x, Rs. 4x and Rs. 3x respectively.
Then, 4x - 3x = 1000
x = 1000.
B's share = Rs. 2x = Rs. (2 x 1000) = Rs. 2000.
Let the shares of A, B, C and D be Rs. 5x, Rs. 2x, Rs. 4x and Rs. 3x respectively.
Then, 4x - 3x = 1000
x = 1000.
B's share = Rs. 2x = Rs. (2 x 1000) = Rs. 2000.
Question: 23 -
Vessels A and B contain mixtures of milk and water in the ratios 4: 5and 5: 1respectively. In what ratio should quantities of the mixture be taken from A and B to form a mixture in which milk to water is in the ratio 5: 4?
-
2: 5
-
4: 3
-
2: 3
-
5: 2
Answer:
5: 2
Solution:
Let the quantity of vessels A and B in the ratio x: y to form a mixture of water and milk in the ratio 4: 5.
Or, Milk: water = 5: 4.
From vessel A, milk: water = 4x/9: 5x/9
From vessel B, milk: water = 5y/6: 1y/6
Now, ATQ quantities of the mixture should be taken from A and B.
Ratio of milk: water = [4x/9 +5y/6]: [5x/9+ 1y/6] = 5/4
Take the LCM of 9 and 6 = 54
Or, [24x + 45y]/54: [30x+9y]/54 = 5/4
Or, [8x + 15 y]: [10x + 3y] = 5/4
Or, [8x + 15y] * 4 = [10x + 3y] * 5
Or, (60-15) y = (50-32) x
Or, 45y = 18x
Or, 5y = 2x
Or, x: y = 5: 2
Hence, the quantity of mixture should be taken from A and B in the ratio 5: 2.
Let the quantity of vessels A and B in the ratio x: y to form a mixture of water and milk in the ratio 4: 5.
Or, Milk: water = 5: 4.
From vessel A, milk: water = 4x/9: 5x/9
From vessel B, milk: water = 5y/6: 1y/6
Now, ATQ quantities of the mixture should be taken from A and B.
Ratio of milk: water = [4x/9 +5y/6]: [5x/9+ 1y/6] = 5/4
Take the LCM of 9 and 6 = 54
Or, [24x + 45y]/54: [30x+9y]/54 = 5/4
Or, [8x + 15 y]: [10x + 3y] = 5/4
Or, [8x + 15y] * 4 = [10x + 3y] * 5
Or, (60-15) y = (50-32) x
Or, 45y = 18x
Or, 5y = 2x
Or, x: y = 5: 2
Hence, the quantity of mixture should be taken from A and B in the ratio 5: 2.
Question: 24 -
In a mixture 60 litres, the ratio of milk and water 2 : 1. If this ratio is to be 1 : 2, then the quantity of water to be further added is:
-
40 litres
-
20 litres
-
60 litres
-
30 litres
Answer:
60 litres
Solution:
Quantity of milk =
60 x
2
litres = 40 litres.
3
Quantity of water in it = (60- 40) litres = 20 litres.
New ratio = 1 : 2
Let quantity of water to be added further be x litres.
Then, milk : water =
40
.
20 + x
Now,
40
=
1
20 + x
2
20 + x = 80
x = 60.
Quantity of water to be added = 60 litres.
Quantity of milk = | 60 x | 2 | litres = 40 litres. | |
3 |
Quantity of water in it = (60- 40) litres = 20 litres.
New ratio = 1 : 2
Let quantity of water to be added further be x litres.
Then, milk : water = | 40 | . | ||
20 + x |
Now, | 40 | = | 1 | ||
20 + x | 2 |
20 + x = 80
x = 60.
Quantity of water to be added = 60 litres.
Question: 25 -
If 0.75 : x :: 5 : 8, then x is equal to:
-
1.25
-
1.30
-
1.12
-
1.2
Answer:
1.2
Solution:
(x x 5) = (0.75 x 8) x =6/5= 1.205
(x x 5) = (0.75 x 8) x =6/5= 1.205