If i have 1/5 < 1/k-1 < 1/2
How do we say that k-1 = 3 or 4 ??????
I see k-1 is less than 2 and more than 5, because on the number line k-1 is more than 5 and less than 2.
I am getting the opposite of the OE.
Help!
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- uttam.albela
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Let us do 1/(1/5), 1/(1/k-1) and 1/(1/2).heshamelaziry wrote:If i have 1/5 < 1/k-1 < 1/2
How do we say that k-1 = 3 or 4 ??????
I see k-1 is less than 2 and more than 5, because on the number line k-1 is more than 5 and less than 2.
I am getting the opposite of the OE.
When we do these operations the comparison signs will reverse. For example : 4>3 But 1/4 < 1/3
So we have
5 > k-1 > 2
know we can see that k =5, 4.
- grockit_jake
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Because you are looking at the denominator, you actually have to switch the inequality signs.
For example: 1/5 < 1/2 but 5>2. When you take the inverse, the order switches.
For our original problem
1/5 < 1/k-1 < 1/2
means 5 > k-1 > 2, so 6>k>3.
Notice the fractions were flipped, as well as the direction of the inequality. Then you just solve for k.
For example: 1/5 < 1/2 but 5>2. When you take the inverse, the order switches.
For our original problem
1/5 < 1/k-1 < 1/2
means 5 > k-1 > 2, so 6>k>3.
Notice the fractions were flipped, as well as the direction of the inequality. Then you just solve for k.
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grockit_jake wrote:Because you are looking at the denominator, you actually have to switch the inequality signs.
For example: 1/5 < 1/2 but 5>2. When you take the inverse, the order switches.
For our original problem
1/5 < 1/k-1 < 1/2
means 5 > k-1 > 2, so 6>k>3.
Notice the fractions were flipped, as well as the direction of the inequality. Then you just solve for k.
i guess the options in the answers will help make that assumption.