In a primary school, the parents were asked the number of hours they spend per day in helping their children to do homework. There were 90 parents who helped \frac{1}{2} hour to 1\frac{1}{2}hours. The distribution of parents according to the time for which they said they helped is given in the adjoining figure; 20% helped for more than 1\frac{1}{2}  hours; 30% helped for   \frac{1}{2}  hour to 1\frac{1}{2}   hours; 50% did not help at all. 

Using this, answer the following :

(i) How many parents were surveyed? 

 

 

Answers (1)

Let the number of parents surveyed be X.

30% of them helped for for   \frac{1}{2}  hour to 1\frac{1}{2}   hours.

In total, there were 90 such parents.

\therefore 30% of X = 90

\Rightarrow \frac{30}{100}\times X = 90 \\ \Rightarrow X = 90\times100 /30 = 300

Therefore, There were total of 300 parents who were surveyed.

Most Viewed Questions

Preparation Products

Knockout NEET 2024

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 39999/-
Buy Now
Knockout NEET 2025

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 45000/-
Buy Now
NEET Foundation + Knockout NEET 2024

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 54999/- ₹ 42499/-
Buy Now
NEET Foundation + Knockout NEET 2024 (Easy Installment)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 3999/-
Buy Now
NEET Foundation + Knockout NEET 2025 (Easy Installment)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 3999/-
Buy Now
Boost your Preparation for JEE Main with our Foundation Course
 
Exams
Articles
Questions