| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.17 |
| Score | 0% | 63% |
What is the least common multiple of 6 and 12?
| 12 | |
| 21 | |
| 35 | |
| 42 |
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.
What is 9x6 + x6?
| 10x12 | |
| -8x-6 | |
| 8x-6 | |
| 10x6 |
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:
9x6 + 1x6
(9 + 1)x6
10x6
A circular logo is enlarged to fit the lid of a jar. The new diameter is 50% larger than the original. By what percentage has the area of the logo increased?
| 20% | |
| 22\(\frac{1}{2}\)% | |
| 25% | |
| 15% |
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 50% the radius (and, consequently, the total area) increases by \( \frac{50\text{%}}{2} \) = 25%
A triathlon course includes a 400m swim, a 50.3km bike ride, and a 6.3km run. What is the total length of the race course?
| 29.8km | |
| 37.1km | |
| 64km | |
| 57km |
To add these distances, they must share the same unit so first you need to first convert the swim distance from meters (m) to kilometers (km) before adding it to the bike and run distances which are already in km. To convert 400 meters to kilometers, divide the distance by 1000 to get 0.4km then add the remaining distances:
total distance = swim + bike + run
total distance = 0.4km + 50.3km + 6.3km
total distance = 57km
What is \( \frac{8}{2} \) + \( \frac{2}{8} \)?
| 1 \( \frac{6}{13} \) | |
| 2 \( \frac{5}{9} \) | |
| 2 \( \frac{3}{8} \) | |
| 4\(\frac{1}{4}\) |
To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 2 are [2, 4, 6, 8, 10, 12, 14, 16, 18, 20] and the first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80]. The first few multiples they share are [8, 16, 24, 32, 40] making 8 the smallest multiple 2 and 8 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{8 x 4}{2 x 4} \) + \( \frac{2 x 1}{8 x 1} \)
\( \frac{32}{8} \) + \( \frac{2}{8} \)
Now, because the fractions share a common denominator, you can add them:
\( \frac{32 + 2}{8} \) = \( \frac{34}{8} \) = 4\(\frac{1}{4}\)