Carcass wrote:
Which of the following numbers have a product that is between -1 and 0 ?
Indicate
both of the numbers
□ -20
□ -10
□ \(2^-^4\)
□ \(3^-^2\)
First recognize that 2^(-4) and 3^(-2) are both POSITIVE, whereas -20 and -10 are both NEGATIVE.
So, if we want a product that's between -1 and 0 (i.e., NEGATIVE), we need one positive value and one negative value.
Let's try some pairs:
-20 and 2^(-4)-20 x 2^(-4) = -20 x 1/16
= -20/16
= -5/4
= -1.25
NO GOOD!
-20 and 3^(-2)-20 x 3^(-2) = -20 x 1/9
= -20/9
= -2 2/9
NO GOOD!
-10 and 2^(-4)-10 x 2^(-4) = -10 x 1/16
= -10/16
= -5/8
= -0.375
PERFECT!
The answer is -10 and 2^(-4)
ASIDE: Also, the product of -10, 2^(-4) and 3^(-2) works as well.
-10 x 2^(-4) x 3^(-2) = -10 x 1/16 x 1/9
= -10/144
This product is also between -1 and 0
Cheers,
Brent
_________________
Brent Hanneson – Creator of greenlighttestprep.com
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