| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.48 |
| Score | 0% | 50% |
What is 7\( \sqrt{6} \) x 3\( \sqrt{2} \)?
| 10\( \sqrt{2} \) | |
| 10\( \sqrt{12} \) | |
| 42\( \sqrt{3} \) | |
| 21\( \sqrt{2} \) |
To multiply terms with radicals, multiply the coefficients and radicands separately:
7\( \sqrt{6} \) x 3\( \sqrt{2} \)
(7 x 3)\( \sqrt{6 \times 2} \)
21\( \sqrt{12} \)
Now we need to simplify the radical:
21\( \sqrt{12} \)
21\( \sqrt{3 \times 4} \)
21\( \sqrt{3 \times 2^2} \)
(21)(2)\( \sqrt{3} \)
42\( \sqrt{3} \)
On average, the center for a basketball team hits 40% of his shots while a guard on the same team hits 60% of his shots. If the guard takes 30 shots during a game, how many shots will the center have to take to score as many points as the guard assuming each shot is worth the same number of points?
| 50 | |
| 45 | |
| 32 | |
| 64 |
guard shots made = shots taken x \( \frac{\text{% made}}{100} \) = 30 x \( \frac{60}{100} \) = \( \frac{60 x 30}{100} \) = \( \frac{1800}{100} \) = 18 shots
The center makes 40% of his shots so he'll have to take:
shots made = shots taken x \( \frac{\text{% made}}{100} \)
shots taken = \( \frac{\text{shots taken}}{\frac{\text{% made}}{100}} \)
to make as many shots as the guard. Plugging in values for the center gives us:
center shots taken = \( \frac{18}{\frac{40}{100}} \) = 18 x \( \frac{100}{40} \) = \( \frac{18 x 100}{40} \) = \( \frac{1800}{40} \) = 45 shots
to make the same number of shots as the guard and thus score the same number of points.
What is \( \frac{4}{3} \) - \( \frac{5}{7} \)?
| \( \frac{4}{21} \) | |
| \(\frac{13}{21}\) | |
| 2 \( \frac{3}{12} \) | |
| \( \frac{3}{7} \) |
To subtract these fractions, first find the lowest common multiple of their denominators. The first few multiples of 3 are [3, 6, 9, 12, 15, 18, 21, 24, 27, 30] and the first few multiples of 7 are [7, 14, 21, 28, 35, 42, 49, 56, 63, 70]. The first few multiples they share are [21, 42, 63, 84] making 21 the smallest multiple 3 and 7 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{4 x 7}{3 x 7} \) - \( \frac{5 x 3}{7 x 3} \)
\( \frac{28}{21} \) - \( \frac{15}{21} \)
Now, because the fractions share a common denominator, you can subtract them:
\( \frac{28 - 15}{21} \) = \( \frac{13}{21} \) = \(\frac{13}{21}\)
\({b + c \over a} = {b \over a} + {c \over a}\) defines which of the following?
distributive property for multiplication |
|
commutative property for division |
|
distributive property for division |
|
commutative property for multiplication |
The distributive property for division helps in solving expressions like \({b + c \over a}\). It specifies that the result of dividing a fraction with multiple terms in the numerator and one term in the denominator can be obtained by dividing each term individually and then totaling the results: \({b + c \over a} = {b \over a} + {c \over a}\). For example, \({a^3 + 6a^2 \over a^2} = {a^3 \over a^2} + {6a^2 \over a^2} = a + 6\).
If a rectangle is twice as long as it is wide and has a perimeter of 42 meters, what is the area of the rectangle?
| 8 m2 | |
| 98 m2 | |
| 128 m2 | |
| 18 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 42 meters so the equation becomes: 2w + 2h = 42.
Putting these two equations together and solving for width (w):
2w + 2h = 42
w + h = \( \frac{42}{2} \)
w + h = 21
w = 21 - h
From the question we know that h = 2w so substituting 2w for h gives us:
w = 21 - 2w
3w = 21
w = \( \frac{21}{3} \)
w = 7
Since h = 2w that makes h = (2 x 7) = 14 and the area = h x w = 7 x 14 = 98 m2