Mrs.Sanders has 80 coins some were 1 dollar coins and the rest were 50 cents coins.The total amount was $50, how much 1 dollar a
1 answer:
Answer:
Mrs. Sanders has 20, 1 dollar coins and 60, 50 cent coins.
Step-by-step explanation:
We are given the following in the question:
Let x be the 1 dollar coins and y be the number of 50 cents coins.
Total number of coins = 80
Thus, we can write the equation:
Total amount = $50
Thus, we can write the equation:
Solving the two equations by elimination, we get,
Thus, Mrs. Sanders has 20, 1 dollar coins and 60, 50 cent coins.
You might be interested in
Answer:
Step-by-step explanation:
Data given and notation
represent the sample mean
represent the sample standard deviation for the sample
sample size
represent the value that we want to test
represent the significance level for the hypothesis test.
t would represent the statistic (variable of interest)
represent the p value for the test (variable of interest)
State the null and alternative hypotheses.
We need to conduct a hypothesis in order to check if the mean weight is less than 4 ounces, the system of hypothesis would be:
Null hypothesis:
Alternative hypothesis:
If we analyze the size for the sample is < 30 and we don't know the population deviation so is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:
(1)
t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".
Calculate the statistic
We can replace in formula (1) the info given like this: