Hello, can someone explain the following:
If 2<a<11 and 3<b<12, then which of the following is NOT true?
1<a+b<23
14<ab<8
7<ba<14
1<b+a<23
24<ab<132
Thanks
Combining Inequalities
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The answer is C.BKNY718 wrote:Hello, can someone explain the following:
If 2<a<11 and 3<b<12, then which of the following is NOT true?
1<a+b<23
14<ab<8
7<ba<14
1<b+a<23
24<ab<132
Thanks
For Addition of a and b.
Take maximum value for maximum range = 11 + 12 = less than 23
And minimum vakue = 1 + 3 = greater than 1
So , A and D are true.
For multiplication the Maximum value can be obtained by multiplying the maximum values greater than 0= 12*11 = less than 132
Mimimum value can be obtained by multiplying th maximum number in the range with the least number on the negative side = 12*(2) = greatert than 24
So, E is true.
For subtraction there will be 2 results:
For ab = Maximum value can be maximum of a minus mimimum of b = 113 = less than 8
and minimum value can be minimum can be minimum of a minus maximum of b = 212 = greater than 14
So, B is true.
For ba = maximum value can be maximum of b minus minimum of a = 12(2) = less than 14
and mimimum value can be minimum of b minus maximum of a = 311 = greater than 8
So, C is not true.
ANS : 7<ba<14
becaz the correct value should be 8<ba<14
to solve these think about the lowest and highest possible value for (ba).
for lowest value b = 3 and a = 11 => ba = 8
becaz the correct value should be 8<ba<14
to solve these think about the lowest and highest possible value for (ba).
for lowest value b = 3 and a = 11 => ba = 8
This time no looking back!!!
Navami
Navami
So these seem to be rules for +,,and * when dealing with inequality values?winniethepooh wrote:The answer is C.BKNY718 wrote:Hello, can someone explain the following:
If 2<a<11 and 3<b<12, then which of the following is NOT true?
1<a+b<23
14<ab<8
7<ba<14
1<b+a<23
24<ab<132
Thanks
For Addition of a and b.
Take maximum value for maximum range = 11 + 12 = less than 23
And minimum vakue = 1 + 3 = greater than 1
So , A and D are true.
For multiplication the Maximum value can be obtained by multiplying the maximum values greater than 0= 12*11 = less than 132
Mimimum value can be obtained by multiplying th maximum number in the range with the least number on the negative side = 12*(2) = greatert than 24
So, E is true.
For subtraction there will be 2 results:
For ab = Maximum value can be maximum of a minus mimimum of b = 113 = less than 8
and minimum value can be minimum can be minimum of a minus maximum of b = 212 = greater than 14
So, B is true.
For ba = maximum value can be maximum of b minus minimum of a = 12(2) = less than 14
and mimimum value can be minimum of b minus maximum of a = 311 = greater than 8
So, C is not true.

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Am not sure, is this a DS Question!BKNY718 wrote:Hello, can someone explain the following:
If 2<a<11 and 3<b<12, then which of the following is NOT true?
1<a+b<23
14<ab<8
7<ba<14
1<b+a<23
24<ab<132
Thanks
i thought it as from PS, so that way i say Option:1 is false! as 3<= a+b <=21
Let me know what's the answer please.

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good question ...C is the correct answerBKNY718 wrote:Hello, can someone explain the following:
If 2<a<11 and 3<b<12, then which of the following is NOT true?
1<a+b<23
14<ab<8
7<ba<14
1<b+a<23
24<ab<132
Thanks