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Ratio
Question 146 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
The third proportional to 38 and 15 is -
(15 $ \times$ 15)/38 | |
(38 $\times$ 15)/2 | |
15/(38 $\times$ 38) | |
(38 $\times$ 38)/15 |
Question 146 Explanation:
Let the third proportional to 38 and 15 be x. \begin{align} & {\text{Then, }} \cr & \Rightarrow 38:15::15:x \cr & \Rightarrow 38x = 15 \times 15 \cr & \Rightarrow x = \frac{{15 \times 15}}{{38}}. \cr\end{align}
Question 147 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
The numbers are in the ratio 3 : 5 and their LCM is 225. The smaller number is =?
45 | |
60 | |
90 | |
75 |
Question 147 Explanation:
| A | : | B | |
| 3 | : | 5 | |
| Let | 3x | : | 5x |
15x = 225
Given
x = 15
∴ A = 15 $\times$ 3 = 45
B = 15 $\times$ 3 = 75
Smaller number is = 45
Question 148 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
If A : B = 1/2 : 3/8, B : C = 1/3 : 5/9 and C : D = 5/6 : 3/4, then the ratio A : B : C : D is
8 : 6 : 10 : 9 | |
4 : 6 : 8 : 10 | |
6 : 4 : 8 : 40 | |
6 : 8 : 9 : 10 |
Question 148 Explanation:
\begin{align} & {\text{A}}:{\text{B}} = \frac{1}{2}:\frac{3}{8} = 4:3, \cr & {\text{B}}:{\text{C}} = \frac{1}{3}:\frac{5}{9} = 3:5, \cr & {\text{C}}:{\text{D}} = \frac{5}{6}:\frac{3}{4} = 10:9 \cr & \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, \, = 5:\frac{9}{2}. \cr & \therefore {\text{A}}:{\text{B}}:{\text{C}}:{\text{D}} \cr & = 4:3:5:\frac{9}{2} \cr & = 8:6:10:9. \cr\end{align}
Question 149 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
Rs. 900 is divided among A, B, C the division is such that 1/2 of A's money = 1/3 of B's money = 1/4 of C's money. Find the amount ( in rupees) received by A, B, C =?
200, 300, 400 | |
350, 450, 100 | |
400, 150, 350 | |
300, 400, 100 |
Question 149 Explanation:
\begin{align} & \Rightarrow \frac{1}{2}{\text{A}} = \frac{1}{3}{\text{B}} = \frac{1}{4}{\text{C}} \cr & \Rightarrow {\text{A}}:{\text{B}}:{\text{C}} \cr & \, \, \, \, \, \, \, \, 2\, \, :3:4{\text{ }} \cr & 2x + 3x + 4x = 900 \cr & \Rightarrow 9x = 900 \cr & \Rightarrow x = 100 \cr & {\text{A}} = 200 \cr & {\text{B}} = 300 \cr & {\text{C}} = 400 \cr\end{align}
Question 150 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
If (4x2 - 3y2) : (2x2 + 5y2) = 12 : 19, then x : y is
2 : 1 | |
3 : 2 | |
2 : 3 | |
1 : 2 |
Question 150 Explanation:
\begin{align} & {\text{ = }}\frac{{4{x^2} - 3{y^2}}}{{2{x^2} + 5{y^2}}} = \frac{{12}}{{19}} \cr & \Rightarrow 19\left( {4{x^2} - 3{y^2}} \right) = 12\left( {2{x^2} + 5{y^2}} \right) \cr & \Rightarrow 76{x^2} - 57{y^2} = 24{x^2} + 60{y^2} \cr & \Rightarrow 52{x^2} = 117{y^2} \cr & \Rightarrow 4{x^2} = 9{y^2} \cr & \Rightarrow \frac{{{x^2}}}{{{y^2}}} = \frac{9}{4} \cr & \Rightarrow {\left( {\frac{x}{y}} \right)^2} = {\left( {\frac{3}{2}} \right)^2} \cr & \Rightarrow \frac{x}{y} = \frac{3}{2} \cr & \therefore x:y = 3:2. \cr\end{align}
There are 150 questions to complete.