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zhenek [66]
2 years ago
8

Däne has a stamp collection. in one boo he has 6 pages with 15 stamps on each page. in another book,he has 9 pages with 20 stamp

s on each page. he gives 25 stamps to a friend. write an equation to show how many stamps dane has left.
Mathematics
1 answer:
galben [10]2 years ago
8 0
6x15= 90

9x20= 180


180+90= 270


270 - 25 = 245        dane has 245 stamps left
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Answer:

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a) The probability that the life of the component is less than or equal to 6000 needs to be equal to 1-P(t>6000).

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P(A)+P(B) = \frac{Na}{Na+Nb} + \frac{Nb}{Na+Nb} = 1

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