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Please help me with this question

Please help me with this question-example-1
User Patrick Gidich
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1 Answer

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Answer:

The sum of 1/6 and 1/7 would be 13/42, or, if you wanted the answer in decimal form rounded to the nearest hundredth, it would be about 0.31.

To find the sum of 1/6 and 1/7, we cannot simply add the numerators together and maintain the same denominator. This is because 1/6 and 1/7 have different denominators, so we don't know which denominator to maintain!

To fix this we need to find a number that is divisible by both 6 and 7. One easy way to do this is to multiply the two numbers together:

6 x 7 = 42

If we were to change the denominator to 42 for each fraction, we could add the numerators together and maintain a denominator of 42. However, this means we must change the numerator of each fraction along with its denominator.

Let's start with 1/6. We can multiply 6 by 7 to obtain 42, but this means we also have to multiply 1 by 7 to keep the fraction proportionate. If the fraction does not maintain the same proportion, it will be a completely different fraction!

We know that 1 x 7 = 7, so it is safe to say that 1/6 is equal to 7/42.

We can apply the same logic to 1/7. Since 7 x 6 is 42 we need to multiply 1 by 6 along with 7. Note: you cannot multiply each number by 7 this time, because 7 x 7 would be 49, not 42. In multiplying the numerator and denominator by 6 we know that 1/7 = 6/42.

Now we have an equation of:

6/42 + 7/42

Now we can add it as we would normally by adding the numerators and keeping the denominator to get:

6/42 + 7/42 = 13/42

If you needed the answer in decimal form it would be about 0.3095238095, or 0.31 rounded to the nearest hundredth.

I hope this helped.

User Tbruyelle
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