Question

4. 96% of the cost of a TV is 10464. What is its total cost?
5. 70% of the students in a school are boys and the number of girls is 504. Find the number of
6. An ore contains 12% copper. How many kilograms of the ore are required to get 69 kg
boys in the school.​

Answer 1

Step-by-step explanation:

$\huge \tt \pink{ \underline{Answer}}$

$\large \tt \green{Answer \: 1}$

☛Let the cost of TV be x

☛96% of the cost of a TV = ₹ 10464

☛∴ 96 % of ₹ x = ₹ 10464

(96/100) × x = 10464

x = (10464 × 100) / (96)

x = 10900

☛ Hence, the cost of TV is ₹

$\large \tt \red{Answer \: 2}$

☛Let the total number of students be 100 Let x kg be the amount of the required ore.

☛Then, as per the question 70% of boys = 70

☛Number of girls = 30

☛Now, total number of students when the number of girls is 30 = 100

☛Then, total number of students when the number of girls is 504

= (100/30) × 504

= 1680

☛ Total number of boys = 1680 – 504 = 1176

∴The number of boys in a school is 1176.

$\large \tt \orange{Answer \: 3}$

☛Let x kg be the amount of the required ore.

☛Then, 12% of x kg = 69 kg

☛12/100 × 69 kg

☛ 575 kg

☛Hence, 575 kg of ore is required to get 69 kg of copper.