| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.12 |
| Score | 0% | 62% |
What is 6x7 - 7x7?
| -x7 | |
| 13x-14 | |
| x7 | |
| 13x14 |
To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so subtract the coefficients and retain the base and exponent:
6x7 - 7x7
(6 - 7)x7
-x7
What is \( \frac{4}{9} \) - \( \frac{2}{15} \)?
| 2 \( \frac{2}{10} \) | |
| 2 \( \frac{1}{4} \) | |
| 1 \( \frac{1}{45} \) | |
| \(\frac{14}{45}\) |
To subtract these fractions, first find the lowest common multiple of their denominators. The first few multiples of 9 are [9, 18, 27, 36, 45, 54, 63, 72, 81, 90] and the first few multiples of 15 are [15, 30, 45, 60, 75, 90]. The first few multiples they share are [45, 90] making 45 the smallest multiple 9 and 15 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{4 x 5}{9 x 5} \) - \( \frac{2 x 3}{15 x 3} \)
\( \frac{20}{45} \) - \( \frac{6}{45} \)
Now, because the fractions share a common denominator, you can subtract them:
\( \frac{20 - 6}{45} \) = \( \frac{14}{45} \) = \(\frac{14}{45}\)
Which of the following is not an integer?
\({1 \over 2}\) |
|
1 |
|
-1 |
|
0 |
An integer is any whole number, including zero. An integer can be either positive or negative. Examples include -77, -1, 0, 55, 119.
Cooks are needed to prepare for a large party. Each cook can bake either 5 large cakes or 11 small cakes per hour. The kitchen is available for 4 hours and 29 large cakes and 410 small cakes need to be baked.
How many cooks are required to bake the required number of cakes during the time the kitchen is available?
| 7 | |
| 8 | |
| 12 | |
| 6 |
If a single cook can bake 5 large cakes per hour and the kitchen is available for 4 hours, a single cook can bake 5 x 4 = 20 large cakes during that time. 29 large cakes are needed for the party so \( \frac{29}{20} \) = 1\(\frac{9}{20}\) cooks are needed to bake the required number of large cakes.
If a single cook can bake 11 small cakes per hour and the kitchen is available for 4 hours, a single cook can bake 11 x 4 = 44 small cakes during that time. 410 small cakes are needed for the party so \( \frac{410}{44} \) = 9\(\frac{7}{22}\) cooks are needed to bake the required number of small cakes.
Because you can't employ a fractional cook, round the number of cooks needed for each type of cake up to the next whole number resulting in 2 + 10 = 12 cooks.
If there were a total of 450 raffle tickets sold and you bought 13 tickets, what's the probability that you'll win the raffle?
| 14% | |
| 11% | |
| 3% | |
| 18% |
You have 13 out of the total of 450 raffle tickets sold so you have a (\( \frac{13}{450} \)) x 100 = \( \frac{13 \times 100}{450} \) = \( \frac{1300}{450} \) = 3% chance to win the raffle.