**Answer:**

a) 21.2%

b) $176.05 or more

c) 15.87%

**Step-by-step explanation:**

We are** given the following **information in the question:

Mean, μ = $155

Standard Deviation, σ = $25

We are given that the distribution of spending amounts is a bell shaped distribution that is a** normal distribution.
**

**Formula:
**

**a) P(spends more than $175 per week on groceries)
**

P(x > 175)

Calculation the value from standard normal z table, we have,

**b) P(X > x) = 0.2
**

We have to find the value of x such that the probability is 0.2

P(X > x)

Calculation the value from standard normal z table, we have,

A consumer has to spend approximately $176.05 or greater to be in the top 20% of the distribution.

**c) My family spends on average $130 dollars on groceries.**

P(less than $130)

Calculation the value from standard normal z table, we have,

Thus, my family percentile is 15.87%