Asmakan wrote:
Which 3 of the following answers, when multiplied by each other, yield a product less than -1?
A. \(-\frac{15}{17}\)
B. \(-\frac{18}{19}\)
C. \(-\frac{23}{22}\)
D. \(-\frac{17}{16}\)
What is the best strategy here that helps us to reach the right choice quickly ?
The first thing to note is that all four values are NEGATIVE.
So the product of three of those values is guaranteed to be negative.
In order for the product to be less than -1, we want to choose three values with the
greatest magnitudeFor this reason, let's just ignore the signs and pretend we're dealing with strictly positive values.
We can immediately see that (C) 23/22 and (D) 17/16 are both greater than one. So, we'll need C and D have part of our product.
We're left with 15/17 and 18/19
Since 18/19 has a greater magnitude than 15/17, we need 18/19 (B) as part of our product
Answer: B, C, D
Cheers,
Brent