Multiplication of Integers

Q.

A certain freezing process requires that room temperature be lowered from $40$ degree Celsius at rate of $5$degree Celsius every hour what will be the room temperature $10$hours after the process begins?

Q.

Find the product, using suitable properties: $\left(-57\right)\times \left(-19\right)+57$

Q.

Find the product, using suitable properties: $\left(-17\right)\times \left(-29\right)$

Q.

A cement company earns a profit of ₹ $8$ per bag of white cement sold and a loss of ₹ $5$ per bag of grey cement sold. The company sells $3,000$ bags of white cement and $5,000$bags of grey cement in a month. What is its profit or loss?

Q.

Evaluate the following: $\left[\left(-36\right)÷12\right]÷3$

Q. Farmer Mahesh has 125 chicken coops in his farm. Each coop has 5 chickens in it. Every day, each chicken lays 16 eggs. How many eggs does farmer Mahesh collect altogether each day?
[2 marks]

Q.

Find the product, using suitable properties: $\left(-41\right)\times 102$

Q.

The product of two whole numbers is always a whole number.

1. False

2. True

Q. What will be the sign of the product if we multiply together
(i) 8 negative integers and 1 positive integer?
(ii) 21 negative integers and 3 positive integers?
(iii) 199 negative integers and 10 positive integers?

Q.

A fruit seller sells apples and oranges. If he sells each apple at a profit of $Rs5$ and each orange at a loss of $Rs2$, what will be his net profit or loss if he sells

$200$ apples and $500$ oranges

Q.

Product of two negative integers is:

1. Always positive

2. Always negative

3. Both positive and negative

4. Either positive or negative

Q.

Write the numerals for the following

(a) Forty six lakh, five thousands, seven hundred and ninety

(b) Fifty three crore, four lakh, three thousand and eight.

Q.

Find the following product:$9\times (-3)\times (-6)$

Q. Question 5
The temperature at 12 noon was ${10}^{\circ }C$ above zero. If it decreases at the rate of $2^{\circ }C$ per hour until midnight, at what time would the temperature be $8^{\circ }C$ below zero? What would be the temperature at mid-night?

Q.

Using Nikhilam Sutra, find 12 x 13

1. 156
2. 143
3. 146
4. 153

Q.

Mental maths questions :

If, 11, 11 =4

22, 22 = 16

33, 33 = 36

44, 44 = 64

55, 55 = ??

Q.

Question 129

The given table shows the freezing points in ${}^{o}F$ of different gases at sea level. Convert each of these into ${}^{o}C$ to the nearest integral value using the relation and complete the table, $C=\frac{5}{9}(F-32)$
$\begin{array}{ccc}& & \\ \text{Gas}& \text{Freezing point at sea level}{(}^{o}F)& \text{Freezing point at sea level}{(}^{o}C)\\ \text{Hydrogen}& -435& \\ \text{Krypton}& -251& \\ \text{Oxygen}& -369& \\ \text{Helium}& -458& \\ \text{Argon}& -309& \end{array}$

Q.

Solve:

(i) $2-\frac{3}{5}$

(ii) $4+\frac{7}{8}$

(iii) $\frac{3}{5}+\frac{2}{7}$

(iv) $\frac{9}{11}-\frac{4}{15}$

(v) $\frac{7}{10}+\frac{2}{5}+\frac{3}{2}$

(vi) $2\frac{2}{3}+3\frac{1}{2}$

(vii) $8\frac{1}{2}-3\frac{5}{8}$

Q. What is the multiplicative identity of the sum of the first 5 whole numbers.

Q.

If we multiply ________ number of negative integers, then the resulting integer is positive. Fill in the blanks to make the statement true.

Q. Divide:
(-117) by (-9)

Q.

15 Integers are multiplied together. If 10 of them are positive and 5 are negative, then the sign of their product will be negative.

1. True

2. False

Q. A submarine descends from surface of the water at a speed of (30) m per minute. How far the submarine will be from the surface of water after 20 minutes? [ Take the descending distance as a negative integer]

1. (-50) m
2. (-600)m
3. (-10) m
4. (-200) m

Q. In a class test (+3) marks are given for every correct answer and (−2) marks are given for every incorrect answer and no marks for not attempting any question. Rakesh scores 18 marks by attempting16 questions. How many questions has he attempted correctly and how many has he attempted incorrectly? [4 MARKS]

Q. The value of
$13.01\times 5.01=$

1. $6518.01$
2. $651.801$
3. $6.51801$
4. $65.1801$

Q. Choose the correct option for the following.
(-1) x (-1) x (-1) x (-1) x ... 80 times = ___

1. 1
2. -1
3. 80
4. -80

Q.

The product of two integers is 72. If one of them is -12, then find the other.

1. 6

2. 0

3. 12

4. -6

Q.

Question 7(iii)
In a class test containing 10 questions, 5 marks are awarded for every correct answer and (−2) marks are awarded for every incorrect answer and 0 for questions not attempted.
Henna gets two correct and five incorrect answers out of seven questions she attempts. What is her score?

Q.

If p = −2, find the value of:

(i) 4p + 7

(ii) −3p² + 4p + 7

(iii) −2p³ − 3p² + 4p + 7

Q.

Use the sign of >, < or = in the blank to make the statement true.

(-4 $\times$ 2) + 10 __ (6 - 7) $\times$ -2