A and E maths questions
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In the diagram, O is the centre of a wheel of circumference 125 cm. The points X, Y and Z are on the circumference of the wheel and the length of the minor arc XY is 16 cm. Calculate the area of the major segment XYZ. Before this question, we were asked to find the acute angle XOY and also radius of the wheel.
Correct answer is 1230 cm3
The number of bacteria in aculture grows exponentially according to an equation given by N = Z e^kt where t is the time elapsed and Z is the intial no. the population of bacteria is recorded to increase from 1 million to 5 million in 4 hours.
Calculate value of Z and hence find k. (ans key: k = 0.402)
Can't find value of Z somehow... did sub in all the available values but still can't solve this
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Hi,
Question: The number of bacteria in aculture grows exponentially according to an equation given by N = Z e^kt where t is the time elapsed and Z is the intial no. the population of bacteria is recorded to increase from 1 million to 5 million in 4 hours.
Calculate value of Z and hence find k. (ans key: k = 0.402)
Approach:
At t = 0, Z = 1,000,000.
At t = 4, 1,000,000 e^(4k) = 5,000,000, from which k can be solved.
Thanks!Cheers,
Wen Shih -
Hi, in the later part of the question, i was asked to determine no. of bacteria after 1 day. My answer is 1.5625 X 10^10 but the answer is 10^6, but still, i believe my answer is right. Could someone help me check up on this? thanks
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Hi,
Your answer of 1.5625 x 10^10 is correct, bravo!
Cheers,
Wen Shih