Question

What will be the sign of the product if we multiply
1) 10 negative integers and 5 positive integers
2) 6 negative integers and 9 positive integers

Answer 1

1) positive
2)positive

Answer 2

1. (-1 *-1) *(-1 *-1) *(-1 *-1) *(-1 *-1) *(-1 *-1) * 1 * 1 * 1 * 1 * 1  
    = +1 *+1 *+1 *+1 *+1 *+1 *+1 *+1 *+1 * +1
    = +1 or an positive answer....

2. (-1 *-1) *(-1 *-1) *(-1 *-1) * +1 * +1 * +1 * +1 * +1 * +1 * +1 * +1 * +1 * +1
    = +1 *+1 *+1 *+1 *+1 *+1 *+1 *+1 *+1 * +1 * +1 * +1 * +1 
    = +1 or an positive answer.....


Hope this helps you.....