Question

Eighteen integers are multiplied together. What will be the sign if:
a) 15 of them are negative and 3 are positive
b) 9 of them are positive and rest are negative
c) All are negative
Explain with examples

Answer 1

Step-by-step explanation:

Since out of eighteen integers, 15 of them are negative, which is odd number. Hence, sign of product will be negative (-). Since out of eighteen integers 12 of them are negative, which is even number.

Answer 2

1) Negative

2) Positive

3) Negative

4) Positive

Step-by-step explanation:

1) Since, 15 numbers are negative and 15

is odd. If a negative integer is multiplied

odd number of times product is always

negative.

2) Since, 12 numbers are positive and 12

is even. If a negative number is multiplied

even number of times product is always

positive.

3) Since, 9 are positive and thus 9 will be

negative because total no. of integers

are 18. 9 is also and odd number. If

a negative integer is multiplied odd

number of times product is always

negative.

4) Since, all 18 integers are odd and 18 is

an even number. If a negative number is

multiplied even number of times product

is always positive.