To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 3 are [3, 6, 9, 12, 15, 18, 21, 24, 27, 30] and the first few multiples of 7 are [7, 14, 21, 28, 35, 42, 49, 56, 63, 70]. The first few multiples they share are [21, 42, 63, 84] making 21 the smallest multiple 3 and 7 share.

Next, convert the fractions so each denominator equals the lowest common multiple:

\( \frac{3 x 7}{3 x 7} \) + \( \frac{6 x 3}{7 x 3} \)

\( \frac{21}{21} \) + \( \frac{18}{21} \)

Now, because the fractions share a common denominator, you can add them:

\( \frac{21 + 18}{21} \) = \( \frac{39}{21} \) = 1\(\frac{6}{7}\)

The first few multiples of 6 are [6, 12, 18, 24, 30, 36, 42, 48, 54, 60] and the first few multiples of 12 are [12, 24, 36, 48, 60, 72, 84, 96]. The first few multiples they share are [12, 24, 36, 48, 60] making 12 the smallest multiple 6 and 12 have in common.

A number with an exponent (b^e) consists of a base (b) raised to a power (e). The exponent indicates the number of times that the base is multiplied by itself. A base with an exponent of 1 equals the base (b¹ = b) and a base with an exponent of 0 equals 1 ( (b⁰ = 1).

April scored 96% on the test meaning she earned 96% of the possible points on the test. There were 280 possible points on the test so she earned 280 x 0.96 = 268 points. Each question is worth 4 points so she got \( \frac{268}{4} \) = 67 questions right.

To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so add the coefficients and retain the base and exponent:

6a⁷ + 2a⁷
(6 + 2)a⁷
8a⁷