Properties of Integers

Complete the following: $\left(-25\right)÷\left(-1\right)=$ _____

An elevator descends into a mine shaft at the rate of $6$ metres per minute. If the descent starts from $10 \mathrm{m}$ above the ground level, how long will it take to reach $-350 \mathrm{m}$.

In a class test $(+3)$ marks are given for every correct answer and $\left(-2\right)$ marks are given for every incorrect answer and no marks for not attempting any question.

Mohini scores $\left(-5\right)$ marks in his test, thought she has got $7$ correct answers. How many questions has she attempted incorrectly?

In a class test $(+3)$ marks are given for every correct answer and $\left(-2\right)$ marks are given for every incorrect answer and no marks for not attempting any question.

Radika scored $20$ mark. If she has got $12$ correct answers, how many questions has she attempted incorrectly?

Verify that, $\left[(-5\times 2)\times 3\right]=\left(-5\right)\times \left[2\times 3\right]$.

Find the product of  $8\times 53\times \left(-125\right)$, by using the suitable property.

Take at least five pairs of integers and see if the subtraction of integers is commutative.

Take at least five pairs of integers and check whether they are closed under the division.

Take at least $5$ pairs of integers and see if the division of integers is commutative.

Find the answer of the following:
$\left(13\right)÷(-1)$

Find the answer:
$-13÷1$

Find the answer of the following:
$-25÷1$

Check whether $a÷-1=-a$ or not.

Check whether $a÷1=1$ or not

The temperature at 12 noon $10°C$ above zero. If it is decreased at the rate of $2°C$ per hour till midnight, at what time would the temperature be $8°C$ below zero?

A cement company earns a profit of $₹9$ per bag of white cement sold and a loss of $₹5$ per bag of grey cement sold. What is the number of white cement bags it must sell to have neither profit nor loss if the number of grey bag sold $₹5400$?

A cement company earns a profit of $₹9$ per bag of white cement sold and a loss of $₹5$ per bag of grey cement sold. The company sold $7000$ bags of white cement and $6000$ bags of grey cement in a month. What is its profit or loss?

In a class test containing $15$ question, $4$ marks are given for every correct answer and $-2$ marks are given for every incorrect answer. Hema attempts $5$ questions and all are correct. What is her total score?

In a class test containing $15$ question, $4$ marks are given for every correct answer and $-2$ marks are given for every incorrect answer. Bharti attempts all questions but only $9$ answers are correct. What is her total score?

Take at least five examples and check whether the division is associative for integers.