| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.15 |
| Score | 0% | 63% |
If a rectangle is twice as long as it is wide and has a perimeter of 48 meters, what is the area of the rectangle?
| 50 m2 | |
| 98 m2 | |
| 162 m2 | |
| 128 m2 |
The area of a rectangle is width (w) x height (h). In this problem we know that the rectangle is twice as long as it is wide so h = 2w. The perimeter of a rectangle is 2w + 2h and we know that the perimeter of this rectangle is 48 meters so the equation becomes: 2w + 2h = 48.
Putting these two equations together and solving for width (w):
2w + 2h = 48
w + h = \( \frac{48}{2} \)
w + h = 24
w = 24 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 24 - 2w
3w = 24
w = \( \frac{24}{3} \)
w = 8
Since h = 2w that makes h = (2 x 8) = 16 and the area = h x w = 8 x 16 = 128 m2
What is \( \frac{4}{5} \) ÷ \( \frac{2}{5} \)?
| \(\frac{2}{15}\) | |
| \(\frac{1}{8}\) | |
| 2 | |
| \(\frac{2}{63}\) |
To divide fractions, invert the second fraction and then multiply:
\( \frac{4}{5} \) ÷ \( \frac{2}{5} \) = \( \frac{4}{5} \) x \( \frac{5}{2} \)
To multiply fractions, multiply the numerators together and then multiply the denominators together:
\( \frac{4}{5} \) x \( \frac{5}{2} \) = \( \frac{4 x 5}{5 x 2} \) = \( \frac{20}{10} \) = 2
What is the least common multiple of 6 and 14?
| 75 | |
| 69 | |
| 43 | |
| 42 |
The first few multiples of 6 are [6, 12, 18, 24, 30, 36, 42, 48, 54, 60] and the first few multiples of 14 are [14, 28, 42, 56, 70, 84, 98]. The first few multiples they share are [42, 84] making 42 the smallest multiple 6 and 14 have in common.
18 members of a bridal party need transported to a wedding reception but there are only 3 5-passenger taxis available to take them. How many will need to find other transportation?
| 4 | |
| 3 | |
| 1 | |
| 8 |
There are 3 5-passenger taxis available so that's 3 x 5 = 15 total seats. There are 18 people needing transportation leaving 18 - 15 = 3 who will have to find other transportation.
How many 2\(\frac{1}{2}\) gallon cans worth of fuel would you need to pour into an empty 15 gallon tank to fill it exactly halfway?
| 6 | |
| 3 | |
| 7 | |
| 4 |
To fill a 15 gallon tank exactly halfway you'll need 7\(\frac{1}{2}\) gallons of fuel. Each fuel can holds 2\(\frac{1}{2}\) gallons so:
cans = \( \frac{7\frac{1}{2} \text{ gallons}}{2\frac{1}{2} \text{ gallons}} \) = 3