| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.03 |
| Score | 0% | 61% |
What is \( \frac{8}{8} \) + \( \frac{8}{12} \)?
| 2 \( \frac{4}{7} \) | |
| 1\(\frac{2}{3}\) | |
| \( \frac{6}{15} \) | |
| 2 \( \frac{4}{24} \) |
To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80] and the first few multiples of 12 are [12, 24, 36, 48, 60, 72, 84, 96]. The first few multiples they share are [24, 48, 72, 96] making 24 the smallest multiple 8 and 12 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{8 x 3}{8 x 3} \) + \( \frac{8 x 2}{12 x 2} \)
\( \frac{24}{24} \) + \( \frac{16}{24} \)
Now, because the fractions share a common denominator, you can add them:
\( \frac{24 + 16}{24} \) = \( \frac{40}{24} \) = 1\(\frac{2}{3}\)
If a mayor is elected with 71% of the votes cast and 77% of a town's 14,000 voters cast a vote, how many votes did the mayor receive?
| 6,468 | |
| 7,115 | |
| 6,037 | |
| 7,654 |
If 77% of the town's 14,000 voters cast ballots the number of votes cast is:
(\( \frac{77}{100} \)) x 14,000 = \( \frac{1,078,000}{100} \) = 10,780
The mayor got 71% of the votes cast which is:
(\( \frac{71}{100} \)) x 10,780 = \( \frac{765,380}{100} \) = 7,654 votes.
If \( \left|a + 1\right| \) - 9 = -3, which of these is a possible value for a?
| -7 | |
| 6 | |
| -4 | |
| 3 |
First, solve for \( \left|a + 1\right| \):
\( \left|a + 1\right| \) - 9 = -3
\( \left|a + 1\right| \) = -3 + 9
\( \left|a + 1\right| \) = 6
The value inside the absolute value brackets can be either positive or negative so (a + 1) must equal + 6 or -6 for \( \left|a + 1\right| \) to equal 6:
| a + 1 = 6 a = 6 - 1 a = 5 | a + 1 = -6 a = -6 - 1 a = -7 |
So, a = -7 or a = 5.
In a class of 20 students, 6 are taking German and 13 are taking Spanish. Of the students studying German or Spanish, 4 are taking both courses. How many students are not enrolled in either course?
| 16 | |
| 10 | |
| 11 | |
| 5 |
The number of students taking German or Spanish is 6 + 13 = 19. Of that group of 19, 4 are taking both languages so they've been counted twice (once in the German group and once in the Spanish group). Subtracting them out leaves 19 - 4 = 15 who are taking at least one language. 20 - 15 = 5 students who are not taking either language.
What is the next number in this sequence: 1, 5, 13, 25, 41, __________ ?
| 61 | |
| 52 | |
| 68 | |
| 56 |
The equation for this sequence is:
an = an-1 + 4(n - 1)
where n is the term's order in the sequence, an is the value of the term, and an-1 is the value of the term before an. This makes the next number:
a6 = a5 + 4(6 - 1)
a6 = 41 + 4(5)
a6 = 61