Question

What is the sign of the product?
Column A
1. (–8) • (6.4) • (–12) • (–0.83)
2. (–10.3) • (–9) • (–0.07) • (0.62)
3. (–0.41) • (–91) • (–2.3) • (–8) • (57)
4. (–15) • (–4) • (1.2) • (9) • (–0.06)
Column B
A.
negative
B.
positive

Answer 1

For each line do this:
1. Count how many NEGATIVE numbers there are (ignoring the positive numbers).
2. An even number of negative numbers gives a positive result.
3. An odd number of negative numbers gives a negative result.

Answer 2

Here is an explanation of the method above.
The rules of signs for multiplication (and division) are:
Two positives or two negatives make a positive.
A positive and a negative make a negative.

If you have an even number of negatives multiplied together, you can arrange them in pairs. Every pair of negatives becomes positive, so the entire product is positive.

If you have an odd number of negatives (i.e., you have 1 negative, or 3 negatives, or 5 negatives, etc.), then if it's only 1 negative, then all positives combine to positive, then the one negative and positive is negative. If you have 3 or more negatives (but an odd number of negatives), then every 2 negatives become a positive, but because you started with an odd number of negatives, there will always be one negative left over. That left over negative multiplied by a positive will be negative.