I can assure you that the GMAT will not require you to calculate 1.18³ to any degree of accuracy.tans wrote:how to find cube of 1.18 for eg quickly?
Are you referring to a specific question?
Cheers,
Brent
cube
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Are you referring to a specific question?
Cheers,
Brent
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Hi tans,
I agree with Brent that you would not be expected to perform that calculation on Test Day. Assuming that you're actually dealing with a GMAT question, there will likely be some other approach/tactic you can use instead of cubing 1.18, including rounding/approximation, eliminating answers that are too big or too small, etc.
For example, 1 < 1.18 < 1.2
1³ = 1
1.2³ = (6/5)(6/5)(6/5) = 216/125 = less than 2
So 1.18³ has to be between 1 and 2.
GMAT assassins aren't born, they're made,
Rich
I agree with Brent that you would not be expected to perform that calculation on Test Day. Assuming that you're actually dealing with a GMAT question, there will likely be some other approach/tactic you can use instead of cubing 1.18, including rounding/approximation, eliminating answers that are too big or too small, etc.
For example, 1 < 1.18 < 1.2
1³ = 1
1.2³ = (6/5)(6/5)(6/5) = 216/125 = less than 2
So 1.18³ has to be between 1 and 2.
GMAT assassins aren't born, they're made,
Rich
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Mathsbuddy
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I agree with the others, but as an approximation, you could try:
1.18^3 < 1.2^3 = (12/10)^3
= 12 x 12 x 12/1000
= 144 x 12/1000
= (1440 + 288)/1000
= 1728/1000 = 1.728
So 1.18^3 will be just below 1.728
1.18^3 < 1.2^3 = (12/10)^3
= 12 x 12 x 12/1000
= 144 x 12/1000
= (1440 + 288)/1000
= 1728/1000 = 1.728
So 1.18^3 will be just below 1.728
