Answer:OK
Step-by-step explanation:
Answer:
check your math
Step-by-step explanation:
The first subtraction was correct:
36 -7 3/4 = 28 1/4
The second subtraction needs to be revisited.
28 1/4 -6 2/4 = 27 5/4 -6 2/4 = 21 3/4
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You can do what you did, but you need to pay attention to the signs.
28 1/4 -6 2/4 = (28 -6) +(1/4 -2/4) = 22 - 1/4 = 21 3/4
The result of subtracting 2/4 from 1/4 is -1/4, not +1/4.
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The length of the first cut piece was 21 3/4 inches.
<span>half-life means you divide by 2
21.6 / 3.6 = 6 hf (hf = half-life)
then you divide by 2^6
6.02 x 10^23 / 2^6 = 9.40625 x 10^21 atoms
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26
3hf ===> 2^3
10.0 / 2^3 = 1.25 gram (remaining)
answer : 10 - 1.25 = 8.75g
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27
128 / 2^n = 2
64 = 2^n
n = 6
24 /6 = 4
4 days is the half-live of the sample
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28
2.5/4.46 of 50% initial mass
(2.5/4.46) x 0.5 x 2 = 0.5605 g
answer: 2 - 0.5605 = 1.4395 g
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29
2^7 = 128
so 7 half-lifes
7* 8040 = 56200 days
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30
the time of 10 half-lifes
= 10 x 0.334s = 3.34s </span><span>
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