Solved Questions of Integers
1. The freezing point of water is 32oF. Tim added potassium and found out that the freezing point went down by 8oF. What was the freezing point of the water with the added potassium?
a) 23o
b) 24o
c) 25o
d) 30o
Answer: b) 24o
Explanation: The freezing point of water = 32oF
After adding potassium to it the freezing point goes down by 8oF. (Since the freezing point goes down it is -8oF)
The freezing point of the water with the added potassium is 32oF - 8oF = 24oF.
2. Solve the following:
i. 4 + (-4)
ii. 3 x 127 = ___ x 3
a) i → 0, ii → 59
b) I → 1, ii → -127
c) i → 0, ii → 127
d) i → 1, ii → -59
Answer: c) i → 0, ii → 127
Explanation: i. 4 + (-4) = 4 - 4 = 0
ii. 3 x 127 = 127 x 3, Changing the position of numbers will not affect the result.
3. Which of the following represents the additive inverse of -8?
a) -8
b) 8
c) -1/8
d) 1/8
Answer: b) 8
Explanation: The additive inverse of a number is the number that when added to the original number, results in zero. The additive inverse of -8 is 8, since (-8) + 8 = 0.
4. A man has $8,000 in his bank account. He withdrew $1,500 and then deposited $3,000. How much money does he have in his bank account now?
a) $5800
b) $6230
c) $7869
d) $9500
Answer: d) $9500
Explanation: The man withdrew $1,500, so his bank account decreased by $1,500 and now has $8,000 - $1,500 = $6,500.
He then deposited $3,000, so his bank account increased by $3,000 and now has $6,500 + $3,000 = $9,500.
Therefore, the man now has $9,500 in his bank account.
5. What is the result of (-4) - (-7)?
a) -11
b) 3
c) -3
d) 11
Answer: b) 3
Explanation: When subtracting a negative number, it is the same as adding the positive value of that number. So, (-4) - (-7) becomes (-4) + 7, which equals 3.
6. If a and b are integers, and a + b = 0, what is the value of a x b?
a) - b
b) - b2
c) - 2b
d) 2ab
Answer: b) -b2
Explanation: If a + b = 0, then we know that a = -b. So, a x b = (-b) x b = -b2, which is always negative.
