There will be a 25 grams left after 3240 years.
The half-life of Radium-226 is 1620 years. If we divide 3240 by 1620 the answer is 2. So that means the amount of Radium-226 will divide in half twice.
100 / 2 = 50 / 2 = 25
A. population in 1975 ........................
Answer:
40 percent
Step-by-step explanation:
All you have to do is divide the numerator by the denominator and then multiply that result with 100
(2000 - 150) / 67
27
(3000 - 400) /6
434
(20 - 7) / .75
17
Answer:
b. Do not reject the null hypothesis
Step-by-step explanation:
Given that two random samples of 40 students were drawn independently from two populations of students. Assuming equal variances
we have the following data.
Sample 1
Mean:
76
Standard deviation:
8
Sample size:
40
Sample 2
Mean:
73
Standard deviation:
7
Sample size:
40

Difference -3.000
Standard error 1.681
95% CI -6.3462 to 0.3462
t-statistic -1.785
DF 78
Significance level P = 0.0782
Since p value >0.05,
b. Do not reject the null hypothesis