So first start out by writing an expression for the cost of the child and the adult separately.
Child:
6 + 1r ($6 + $1 per ride)
Adult:
10 + 1.5r ($10 + $1.50 per ride)
to find how much more the adult will spend, just do Adult Expression - Child Expression which will be:
10 + 1.5r - (6 + 1r) just simplify this
For Part B, use your equation from part A where r = 7
Answer: The critical value for a two-tailed t-test = 2.056
The critical value for a one-tailed t-test = 1.706
Step-by-step explanation:
Given : Degree of freedom : df= 26
Significance level : 
Using student's t distribution table , the critical value for a two-tailed t-test will be :-

The critical value for a two-tailed t-test = 2.056
Again, Using student's t distribution table , the critical value for a one-tailed t-test will be :-

The critical value for a one-tailed t-test = 1.706
Answer:
<h2>h(x) = 14</h2>
Step-by-step explanation:
f(x) + n - translation n units up
f(x) - n - translation n units down
f(x + n) - translation n units to the left
f(x - n) - translation n units to the right
===========================================
g(x) = 21
translation 7 units down: g(x) - 7 = 21 - 7 = 14
The sum of 14 and a number is 14+x
we know that this equals 17, so: 14+x=17.
Let's substract 14 from both sides:
x=17-14
x=3
so the number is 3.