Question

In the general population in the US, identical twins occur at a rate of 30 per 1,000 live births. A survey records 10,000 births during Jan 2018 to Jan 2019 and found 400 twins in total. Which of the following are true? Select one or more: The proportion of twin births during Jan 2018 to Jan 2019 is.03. The proportion of twin births during Jan 2018 to Jan 2019 is.04 The probability of twin births among the general population is.03. The probability of twin births among the general population is.04 n Príobserving a sample proportion of twin births from a random sample of 10,000 live births < 0.04)-0.03 Prlobserving a sample proportion of twin births from a random sample of 10,000 live births Prfobserving a sample proportion of twin births from a random sample of 10,000 live births< Pr(observing a sample proportion of twin births from a random sample of 10,000 live births < 0.04)-0.5 0.03)-0.04 0.03) 0.5.

Answer 1

From the given information, The proportion of twin births in the general population in the US is, 30 1000 0.03 Therefore, the population proportion is 0.03 The proportion of twin births during Jan 2018 to Jan 2019 is 400 10,000 0.04 Therefore, the population proportion is 0.04 Hence, second and third options are corr ect Verification for choic es 5 and 6 The mean and standard deviation is computed as follows mean- p -0.03 (0.03)(0.97) 10000 - V0.00000291 = 0.0017

Probability of sample proportion of twin births from a random sample of 10,000 live births less than or equal to 0.04 is, 0.04) = PIP-S0.04-003 Pq(0.03) (0.97) Pfp 10000 0.01 0.00000291 0.01 0.0017 - P(Zs5.88) Therefore, choices 5 and 6 are incorrect. Verification for choices 7 and 8. From the given information, the sample proportion is 0.04 not 0.03 Therefore, the choices 7 and 8 are incorrect Therefore, following are true statements that are provided (2) The proportion of twin births during Jan 2018 to Jan 2019 is 0.04 (3) The probability of twin births among the general population is 0.03