The area of a circle is given by the formula A = πr² where r is the radius of the circle. The radius of a circle is its diameter divided by two so A = π(\( \frac{d}{2} \))². If the diameter of the logo increases by 70% the radius (and, consequently, the total area) increases by \( \frac{70\text{%}}{2} \) = 35%

By buying two shirts, Ezra will save $33 x \( \frac{20}{100} \) = \( \frac{$33 x 20}{100} \) = \( \frac{$660}{100} \) = $6.60 on the second shirt.

So, his total cost will be
$33.00 + ($33.00 - $6.60)
$33.00 + $26.40
$59.40

The distributive property for division helps in solving expressions like \({b + c \over a}\). It specifies that the result of dividing a fraction with multiple terms in the numerator and one term in the denominator can be obtained by dividing each term individually and then totaling the results: \({b + c \over a} = {b \over a} + {c \over a}\). For example, \({a^3 + 6a^2 \over a^2} = {a^3 \over a^2} + {6a^2 \over a^2} = a + 6\).

To find the average of these 4 numbers add them together then divide by 4:

\( \frac{15 + 7 + 14 + 8}{4} \) = \( \frac{44}{4} \) = 11

The equation for this sequence is:

a_n = a_n-1 + 4(n - 1)

where n is the term's order in the sequence, a_n is the value of the term, and a_n-1 is the value of the term before a_n. This makes the next number:

a₆ = a₅ + 4(6 - 1)
a₆ = 41 + 4(5)
a₆ = 61