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# s2 hypothesis testing.. mark scheme error? Watch

1. Dhriti grows tomatoes. Over a period of time, she has found that there is a probability 0.3 of a ripe tomato having a diameter greater than 4 cm. She decides to try a new fertiliser. In a random sample of 40 ripe tomatoes, 18 have a diameter greater than 4 cm. Dhriti claims that the new fertiliser has increased the probability of a ripe tomato being greater than 4 cm in diameter.

Test Dhriti’s claim at the 5% level of significance. State your hypotheses clearly.

H_0: p = 0.3
H_1: p > 0.3

X ~ Bo(40,0.3)
P(X=>18) = 1 - P(X<=17)
= 0.032

0.032 < 0.05 so it is significant

doesn't this mean you reject H_0? the mark scheme says that there is no evidence to reject H_0, is this correct?

thanks in advance
2. (Original post by ihatestats)
Dhriti grows tomatoes. Over a period of time, she has found that there is a probability 0.3 of a ripe tomato having a diameter greater than 4 cm. She decides to try a new fertiliser. In a random sample of 40 ripe tomatoes, 18 have a diameter greater than 4 cm. Dhriti claims that the new fertiliser has increased the probability of a ripe tomato being greater than 4 cm in diameter.

Test Dhriti’s claim at the 5% level of significance. State your hypotheses clearly.

H_0: p = 0.3
H_1: p > 0.3

X ~ Bo(40,0.3)
P(X=>18) = 1 - P(X<=17)
= 0.032

0.032 < 0.05 so it is significant

doesn't this mean you reject H_0? the mark scheme says that there is no evidence to reject H_0, is this correct?

thanks in advance
I can't see anything wrong with your answer
3. (Original post by ihatestats)
Dhriti grows tomatoes. Over a period of time, she has found that there is a probability 0.3 of a ripe tomato having a diameter greater than 4 cm. She decides to try a new fertiliser. In a random sample of 40 ripe tomatoes, 18 have a diameter greater than 4 cm. Dhriti claims that the new fertiliser has increased the probability of a ripe tomato being greater than 4 cm in diameter.

Test Dhriti’s claim at the 5% level of significance. State your hypotheses clearly.

H_0: p = 0.3
H_1: p > 0.3

X ~ Bo(40,0.3)
P(X=>18) = 1 - P(X<=17)
= 0.032

0.032 < 0.05 so it is significant

doesn't this mean you reject H_0? the mark scheme says that there is no evidence to reject H_0, is this correct?

thanks in advance
I agree too

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