Half of the villagers of a certain village have their own houses. One-fifth of the villagers cultivate paddy. One-third of the villagers are literate. Four-fifth of the villagers are below twenty five. Then, which one of the following is certainly true?
(a)
All the villagers who have their own houses are literate
(b)
Some villagers under twenty five are literate
(c)
A quarter of the villagers who have their own houses cultivate paddy.
(d)
Half of the villagers who cultivate paddy are literate
Explanation
We can start by representing the information given in the problem in a table:
Number of villagers Proportion of villagers
Own houses ? 1/2
Cultivate paddy ? 1/5
Literate ? 1/3
Below 25 years old ? 4/5
Let`s use x to represent the total number of villagers in the village. Then we can fill in the table as follows:
Number of villagers Proportion of villagers
Own houses x/2 1/2
Cultivate paddy x/5 1/5
Literate x/3 1/3
Below 25 years old 4x/5 4/5
Now let`s look at the options:
a) All the villagers who have their own houses are literate: This cannot be true, because we know that only 1/3 of the villagers are literate, and more than half of the villagers have their own houses.
b) Some villagers under twenty five are literate: This must be true, since 1/3 of the villagers are literate, and 4/5 of the villagers are below 25 years old.
c) A quarter of the villagers who have their own houses cultivate paddy: This cannot be determined with the given information. We don`t know anything about the proportion of villagers who cultivate paddy among those who own houses.
d) Half of the villagers who cultivate paddy are literate: This cannot be determined with the given information. We don`t know anything about the literacy rate among those who cultivate paddy.
Therefore, the correct answer is (b) Some villagers under twenty five are literate.