| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.98 |
| Score | 0% | 60% |
What is \( 2 \)\( \sqrt{48} \) - \( 2 \)\( \sqrt{3} \)
| 4\( \sqrt{48} \) | |
| 0\( \sqrt{16} \) | |
| 4\( \sqrt{144} \) | |
| 6\( \sqrt{3} \) |
To subtract these radicals together their radicands must be the same:
2\( \sqrt{48} \) - 2\( \sqrt{3} \)
2\( \sqrt{16 \times 3} \) - 2\( \sqrt{3} \)
2\( \sqrt{4^2 \times 3} \) - 2\( \sqrt{3} \)
(2)(4)\( \sqrt{3} \) - 2\( \sqrt{3} \)
8\( \sqrt{3} \) - 2\( \sqrt{3} \)
Now that the radicands are identical, you can subtract them:
8\( \sqrt{3} \) - 2\( \sqrt{3} \)In a class of 24 students, 8 are taking German and 8 are taking Spanish. Of the students studying German or Spanish, 2 are taking both courses. How many students are not enrolled in either course?
| 10 | |
| 23 | |
| 18 | |
| 12 |
The number of students taking German or Spanish is 8 + 8 = 16. Of that group of 16, 2 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 16 - 2 = 14 who are taking at least one language. 24 - 14 = 10 students who are not taking either language.
What is \( \frac{-2a^6}{9a^2} \)?
| -\(\frac{2}{9}\)a\(\frac{1}{3}\) | |
| -4\(\frac{1}{2}\)a8 | |
| -\(\frac{2}{9}\)a4 | |
| -\(\frac{2}{9}\)a-4 |
To divide terms with exponents, the base of both exponents must be the same. In this case they are so divide the coefficients and subtract the exponents:
\( \frac{-2a^6}{9a^2} \)
\( \frac{-2}{9} \) a(6 - 2)
-\(\frac{2}{9}\)a4
A circular logo is enlarged to fit the lid of a jar. The new diameter is 65% larger than the original. By what percentage has the area of the logo increased?
| 27\(\frac{1}{2}\)% | |
| 20% | |
| 32\(\frac{1}{2}\)% | |
| 22\(\frac{1}{2}\)% |
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 65% the radius (and, consequently, the total area) increases by \( \frac{65\text{%}}{2} \) = 32\(\frac{1}{2}\)%
If a car travels 180 miles in 3 hours, what is the average speed?
| 60 mph | |
| 20 mph | |
| 35 mph | |
| 55 mph |
Average speed in miles per hour is the number of miles traveled divided by the number of hours:
speed = \( \frac{\text{distance}}{\text{time}} \)