S K Gupta and Anubhuti Gangal Solutions for Exercise 5: EXERCISE 1(E)

Reena climbs up $5$stairs every second and then climbs down $2$stairs over the next second. How many seconds will she take to climb $60$stairs?

Start with the integer $-8$. Add $-12$ to it, subtract $10$ from the result. Divide the result by $+3$ and multiply the answer by $-2$. What do you get?

Arnav had $₹20$ with him. He spent $₹ 8$ on Monday, got $₹5$ as pocket money on Tuesday, gave a $₹7$loan to a friend on Wednesday, ate an icecream worth $₹10$ on Thursday, received a reward of $₹5$ from his grandfather on Friday. How much does he have on Sunday, if his friend repays the loan on Saturday?

A submarine left the surface of the water at the rate of $-2$ metres per second. At that rate, how long would it take the submarine to reach $-60$ meters level.

The deep freezer of a sweet shop should be set at $-12 °\mathrm{C}$. It is set at $-18°\mathrm{C}$ by mistake. What is the difference between these temperature settings?

A hiker is descending $152 \mathrm{m}$ every $8$ minutes. What will be hikers change in elevation in half an hour? Write as an integer.

In a test, $(+4)$ marks are given for every correct answer and $(-2)$ marks for every wrong answer. Rohit answered all the questions and scored $68$ marks. $25$of Rohit's answers were correct. How many of the questions he attempted were incorrect?

Mt. Everest is at a height of $8850 \mathrm{m}$. Its base is at an elevation of $5400 \mathrm{m}$. The temperature here drops at the rate of $1$ degree per $100$ metres. If the temperature at the base is $-5°\mathrm{C}$, what is the temperature at the top ?
[Hint. Temperature at base is more than temperature at top]