| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.60 |
| Score | 0% | 52% |
What is \( \frac{3}{2} \) + \( \frac{6}{4} \)?
| \( \frac{7}{4} \) | |
| 1 \( \frac{7}{12} \) | |
| 3 | |
| 2 \( \frac{1}{4} \) |
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 4 are [4, 8, 12, 16, 20, 24, 28, 32, 36, 40]. The first few multiples they share are [4, 8, 12, 16, 20] making 4 the smallest multiple 2 and 4 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{3 x 2}{2 x 2} \) + \( \frac{6 x 1}{4 x 1} \)
\( \frac{6}{4} \) + \( \frac{6}{4} \)
Now, because the fractions share a common denominator, you can add them:
\( \frac{6 + 6}{4} \) = \( \frac{12}{4} \) = 3
What is \( 6 \)\( \sqrt{18} \) + \( 7 \)\( \sqrt{2} \)
| 42\( \sqrt{2} \) | |
| 13\( \sqrt{9} \) | |
| 25\( \sqrt{2} \) | |
| 42\( \sqrt{18} \) |
To add these radicals together their radicands must be the same:
6\( \sqrt{18} \) + 7\( \sqrt{2} \)
6\( \sqrt{9 \times 2} \) + 7\( \sqrt{2} \)
6\( \sqrt{3^2 \times 2} \) + 7\( \sqrt{2} \)
(6)(3)\( \sqrt{2} \) + 7\( \sqrt{2} \)
18\( \sqrt{2} \) + 7\( \sqrt{2} \)
Now that the radicands are identical, you can add them together:
18\( \sqrt{2} \) + 7\( \sqrt{2} \)If a rectangle is twice as long as it is wide and has a perimeter of 54 meters, what is the area of the rectangle?
| 2 m2 | |
| 50 m2 | |
| 162 m2 | |
| 72 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 54 meters so the equation becomes: 2w + 2h = 54.
Putting these two equations together and solving for width (w):
2w + 2h = 54
w + h = \( \frac{54}{2} \)
w + h = 27
w = 27 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 27 - 2w
3w = 27
w = \( \frac{27}{3} \)
w = 9
Since h = 2w that makes h = (2 x 9) = 18 and the area = h x w = 9 x 18 = 162 m2
This property states taht the order of addition or multiplication does not mater. For example, 2 + 5 and 5 + 2 are equivalent.
commutative |
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associative |
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PEDMAS |
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distributive |
The commutative property states that, when adding or multiplying numbers, the order in which they're added or multiplied does not matter. For example, 3 + 4 and 4 + 3 give the same result, as do 3 x 4 and 4 x 3.
The total water usage for a city is 25,000 gallons each day. Of that total, 34% is for personal use and 47% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 3,250 | |
| 8,250 | |
| 1,200 | |
| 1,900 |
47% of the water consumption is industrial use and 34% is personal use so (47% - 34%) = 13% more water is used for industrial purposes. 25,000 gallons are consumed daily so industry consumes \( \frac{13}{100} \) x 25,000 gallons = 3,250 gallons.