I am not sure if the “+” was supposed to go there or if that was just a typo, so I do apologize if this is wrong... but if it doesn’t belong in the equation at all, 20 = 2X is a fairly simply multiplication problem. You are to divide both sides by the 2 and you should get X = 10, because 2 goes into 20, 10 times; and the 2 goes into 2 only once, therefore the 2 now gets cancelled out.
Answer: 20 divided by 2 = 2x divided by 2 is now 10 = X.
Really hope this helps you, have a good day :)
Answer:
r≈6ft
Step-by-step explanation:
Using the formula
C=2πr
Solving forr
r=C
2π=37.68
2·π≈5.99696ft
pls mark as brainliest
Answer:
The requirements for the hypothesis test does satisfied the method for testing the claim that from two population proportions the rate of polio is less for children given the salk vaccine.
Step-by-step explanation:
The percentage of children in the treatment group was:
(201229/401974)*100 = 49.9%
The percentage of children given placebo was:
(200745/401974)*100 = 50.1%
The percentage of children that developed polio in the treatment group:
(33/200745)*100 = 0.0164%
The percentage of children that developed polio in the placebo group:
(115/201229)*100 = 0.0571%
The percentage difference between the two group:
((0.0571-0.0164)/0.0571) = 61.62%
Therefore:
The amount of children used for each group was almost divided into half of the total amount of children. The test revealed although very small percentages of the both group developed polio, 68.62% more children given placebo than the children that was given the salk vaccine. Therefore, the study shows that the rate of polio is less for children given the salk vaccine and the the hypthesis test is satisfied.
Mental way:
415 / 51.9 * 100 = 800 students in the school.
detailed way:
x is the amount of students in the school.
51.9% * x = 415
(divide both sides by 51.9% (or 0.519))
x = 800 students
x + y = 52
x = y - 18
Adding,
2x + y = 52 + y - 18
2x = 34
x = 17
y = x + 18 = 35
Check: x+y = 17+35 = 52, good
Answer: 17 and 35
