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Dvinal [7]
3 years ago
5

A research study was performed to determine if more than 30% of first-grade students at one school have entered Piaget’s concret

e operational stage of development. A p-value of .021 was computed and the researchers rejected the null hypothesis. They concluded that more than 30% of first-grade students at this school have entered the concrete operational stage of development. However, a census actually found that in the population of all first graders at this school, only 28% have entered the concrete operational stage. Which of the following occurred in this scenario?a) Type I errorb) Type II error
Mathematics
1 answer:
suter [353]3 years ago
7 0

Answer:

Type I error

Step-by-step explanation:

A type I error occurs if the null hypothesis is rejected when it is actually true.

Type I                                      Type II

Reject null when true           Fail to reject null when not true

Null hypothesis: ∪ = 30%

Alternative hypothesis: ∪ > 30%

The researchers concluded that more than 30% of first-grade students at this school have entered the concrete operational stage of development and they rejected the null hypothesis.

However, a census actually found that in the population of all first graders at this school, only 28% have entered the concrete operational stage.

A type I error has been made because in actuality the null hypothesis was true but was rejected.

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<h3>Answer:</h3>

1. x + 20

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<h3>Step-by-step explanation:</h3>

• When working with variables and numbers, you have to put the variables first (in alphabetical order) and then the numbers.

• To evaluate an algebraic expression, we find the value of the expression when the variable is replaced by a given number.

• To evaluate an expression, we substitute the given number for the variable in the expression and then simplify the expression using the order of operations.

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