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Ratio
Question 41 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
A bag contains an equal number of one rupee, 50 paise and 25 paise coins. If the total value is Rs. 35, how many coins of each type are there?
18 | |
27 | |
20 | |
15 |
Question 41 Explanation:
Let X coins of each type of there.
Total Value = Rs. 35.
Now,
X + X/2 + X/4 = 35.
4X + 2X + X = 140.
7X = 140.
X = 20
Question 42 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
The ratio of ducks and frogs in a pond is 37 : 39 respectively. The average number of ducks and frogs in the pond is 152. What is the number of frogs in the pond?
148 | |
152 | |
144 | |
156 |
Question 42 Explanation:
Ratio of Ducks and Frogs in Pond,
= 37 : 39.
Average of Ducks and Frogs in Pond,
= 152.
So, total number of Ducks and Frogs in the Pond,
= 2* 152 = 304.
Therefore,
Number of Frogs, = (304 *39)/76 = 156.
Question 43 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
A person bought some rice and wheat for Rs. 380. The ratio of weight of rice and wheat is 4 : 3 and the price equal amount of rice and wheat is in the ratio 5 : 6. The rice was bought of worth =?
Rs. 200 | |
Rs. 300 | |
Rs. 380 | |
Rs. 180 |
Question 43 Explanation:
| Rice | : | Wheat | |||
| Weight | 4 | : | 3 | ||
| Price | 5 | : | 6 | ||
| Total Price | 20 | + | 18 | = | 38 |
1 unit = Rs. 10
∴ Price of total rice
⇒ 20 $\times$ 10 = Rs. 200
Question 44 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
If 2/3 of A=75% of B=0.6 of C, then A:B:C is
9:8:10 | |
3:4:5 | |
4:5:6 | |
2:3:3 |
Question 44 Explanation:
\begin{align} & {\text{According}}\, {\text{to}}\, {\text{thequestion, }} \cr & \left( {\frac{{2A}}{3}} \right) = \left( {\frac{{75B}}{{100}}} \right) = \left( {\frac{{C \times 6}}{{10}}} \right); \cr & {\text{Above}}\, {\text{relation}}\, {\text{gives}}; \cr & \frac{{A \times 2}}{3} = \frac{{B \times 3}}{4} \cr & \to \frac{A}{B} = \frac{9}{8} \cr & {\text{And}}, \cr & \frac{{B \times 3}}{4} = \frac{{C \times 3}}{5} \cr & \to \frac{B}{C} = 8:10 \cr & {\text{Thus, }} \cr & A:B:C = 9:8:10 \cr\end{align}
Question 45 [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER] |
\begin{align} & {\text{Let }}\frac{{\text{a}}}{{\text{b}}}: - \frac{{\text{b}}}{{\text{a}}} = {\text{x}}:{\text{y}}{\text{.}} \cr & {\text{If}}\left( {{\text{x - y}}} \right) = \left\{ {\frac{{\text{a}}}{{\text{b}}}{\text{ + }}\frac{{\text{b}}}{{\text{a}}}} \right\}{\text{, }} \cr & {\text{then x is equal to - }} \cr\end{align}
(a + b)/b | |
None of these | |
(a - b)/a | |
(a + b)/a |
Question 45 Explanation:
\begin{align} & \Rightarrow \frac{x}{y} = \frac{{\left( {\frac{a}{b}} \right)}}{{\left( { - \frac{b}{a}} \right)}} = - \frac{{{a^2}}}{{{b^2}}} \cr & \Rightarrow y = \left( { - \frac{{{b^2}}}{{{a^2}}}} \right)x. \cr & \therefore x - y = \frac{{\text{a}}}{{\text{b}}}{\text{ + }}\frac{{\text{b}}}{{\text{a}}} \cr & \Rightarrow x + \frac{{{b^2}}}{{{a^2}}}x = \frac{{{a^2} + {b^2}}}{{ab}} \cr & \Rightarrow x\left( {\frac{{{a^2} + {b^2}}}{{{a^2}}}} \right) = \frac{{{a^2} + {b^2}}}{{ab}} \cr & \Rightarrow x = \frac{{{a^2}}}{{ab}} = \frac{a}{b}. \cr\end{align}
There are 45 questions to complete.