| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.95 |
| Score | 0% | 59% |
| 0.6 | |
| 4.8 | |
| 5.4 | |
| 1 |
1
If there were a total of 150 raffle tickets sold and you bought 7 tickets, what's the probability that you'll win the raffle?
| 1% | |
| 9% | |
| 5% | |
| 15% |
You have 7 out of the total of 150 raffle tickets sold so you have a (\( \frac{7}{150} \)) x 100 = \( \frac{7 \times 100}{150} \) = \( \frac{700}{150} \) = 5% chance to win the raffle.
What is \( \frac{7}{6} \) - \( \frac{9}{10} \)?
| 1 \( \frac{6}{14} \) | |
| \(\frac{4}{15}\) | |
| \( \frac{2}{5} \) | |
| \( \frac{3}{12} \) |
To subtract these fractions, first find the lowest common multiple of their denominators. The first few multiples of 6 are [6, 12, 18, 24, 30, 36, 42, 48, 54, 60] and the first few multiples of 10 are [10, 20, 30, 40, 50, 60, 70, 80, 90]. The first few multiples they share are [30, 60, 90] making 30 the smallest multiple 6 and 10 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{7 x 5}{6 x 5} \) - \( \frac{9 x 3}{10 x 3} \)
\( \frac{35}{30} \) - \( \frac{27}{30} \)
Now, because the fractions share a common denominator, you can subtract them:
\( \frac{35 - 27}{30} \) = \( \frac{8}{30} \) = \(\frac{4}{15}\)
The total water usage for a city is 30,000 gallons each day. Of that total, 35% is for personal use and 48% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 13,600 | |
| 11,550 | |
| 3,900 | |
| 7,750 |
48% of the water consumption is industrial use and 35% is personal use so (48% - 35%) = 13% more water is used for industrial purposes. 30,000 gallons are consumed daily so industry consumes \( \frac{13}{100} \) x 30,000 gallons = 3,900 gallons.
If \( \left|a - 6\right| \) - 6 = 6, which of these is a possible value for a?
| -16 | |
| 9 | |
| 8 | |
| -6 |
First, solve for \( \left|a - 6\right| \):
\( \left|a - 6\right| \) - 6 = 6
\( \left|a - 6\right| \) = 6 + 6
\( \left|a - 6\right| \) = 12
The value inside the absolute value brackets can be either positive or negative so (a - 6) must equal + 12 or -12 for \( \left|a - 6\right| \) to equal 12:
| a - 6 = 12 a = 12 + 6 a = 18 | a - 6 = -12 a = -12 + 6 a = -6 |
So, a = -6 or a = 18.