What value will come in place of question mark (?) in the following questions?

(?)² + 1 = 212 + 172

The ratio of the sum of two numbers and their difference is 5:1. The ratio of the greater number to the smaller number is-

Directions: Read the given pie and table carefully and answer the following questions.

The pie chart shows the percentage distribution of people who found COVID – 19 positive in four major cities of India from 1^st July to 31^st August 2020 and the table shows the number of people who tested positive in July from these cities.

If the recovery rate is 70% and the death rate is 10% of total tested cases in Chennai at the end of July. How many active cases are on 1st August, if no case is found on that day?

A wire is in the shape of a rectangle. Its length is 42.7m and breadth is 21.8m. If the same wire is re-bent in the shape of a square, what will be the measure of the side of the square?

If books bought at prices from ₹150 to ₹ 300 are sold at prices ranging from ₹ 250 to  ₹350, what is the greatest possible profit that might be made in selling 15 books ?

Shivani purchased five pens for ₹600. She sells these five pens at the rate of ₹50 per pen. What is the approximate lo percentage that Shivani incurred on selling the five pens?

The price of diesel increases by 5% every year. If the current price of diesel is ₹80 per litre, then what will be the price of diesel per litre after 2 years?

Ram has 5 daughters. The average age of these 5 sisters is 28 years. The youngest one is 16 years old. What was the average age of the 4 daughters before the youngest one was born?