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by vk_vinayak » Mon Aug 27, 2012 2:18 am
If p = 5.18r7, what is the result when p is subtracted from p rounded to the nearest thousandth?

Can we find the answer to this problem without the help of options?
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Source: — Problem Solving |

by GaneshMalkar » Mon Aug 27, 2012 4:32 am
vk_vinayak wrote:If p = 5.18r7, what is the result when p is subtracted from p rounded to the nearest thousandth?

Can we find the answer to this problem without the help of options?
Answer is 3 * 10^-4 = 0.0003

Explanation = 5.18(r+1) when rounded to nearest thousand
original number = 5.18r7

so when 5.18(r+1) - 5.18r7 = ((r + 1) * 10 ^ -3) - (r * 10 ^ -3 + 7 * 10 ^ -4)

=> (r * 10 ^ -3 + 1 * 10 ^ -3 - r * 10 ^ -3 - 7 * 10 ^ -4)

=> (10 * 10 ^ -4 - 7 * 10 ^ -4)
=> 3 * 10 ^ -4 = 0.0003
If you cant explain it simply you dont understand it well enough!!!
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by vk_vinayak » Mon Aug 27, 2012 5:59 am
That is correct, but the calculation is lengthy.

I guess we are better off using substitution method.
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