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I am trying to solve d with fractions but I am getting it wrong every time.
My reasoning is the following:
1/2 (1/10^5 + 1/10^4) = 1/2 * (10^-5 + 10^-4)= 1/2(10^-9). Hence 0,5 * 10^-9 which takes me to 0,0005 * 10^-5 not 5,5 * 10^-5
I must be making a terrible assumption but I do not see where. I read Purple Math to try find my knowledge gap.
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ruis
I am trying to solve d with fractions but I am getting it wrong every time.
My reasoning is the following:
1/2 (1/10^5 + 1/10^4) = 1/2 * (10^-5 + 10^-4)= 1/2(10^-9). Hence 0,5 * 10^-9 which takes me to 0,0005 * 10^-5 not 5,5 * 10^-5
I must be making a terrible assumption but I do not see where. I read Purple Math to try find my knowledge gap.
­10^(-5) + 10^(-4) does not equal to 10^(-9).
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Bunuel

ruis
I am trying to solve d with fractions but I am getting it wrong every time.
My reasoning is the following:
1/2 (1/10^5 + 1/10^4) = 1/2 * (10^-5 + 10^-4)= 1/2(10^-9). Hence 0,5 * 10^-9 which takes me to 0,0005 * 10^-5 not 5,5 * 10^-5
I must be making a terrible assumption but I do not see where. I read Purple Math to try find my knowledge gap.
­10^(-5) + 10^(-4) does not equal to 10^(-9).
­True... that would be correct only if we were multipling.... Thanks Bunuel! I always mess up with that property...
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