| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.30 |
| Score | 0% | 66% |
What is \( \frac{8}{5} \) + \( \frac{5}{7} \)?
| \( \frac{9}{35} \) | |
| 1 \( \frac{7}{16} \) | |
| 2\(\frac{11}{35}\) | |
| 1 \( \frac{7}{10} \) |
To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 5 are [5, 10, 15, 20, 25, 30, 35, 40, 45, 50] 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 [35, 70] making 35 the smallest multiple 5 and 7 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{8 x 7}{5 x 7} \) + \( \frac{5 x 5}{7 x 5} \)
\( \frac{56}{35} \) + \( \frac{25}{35} \)
Now, because the fractions share a common denominator, you can add them:
\( \frac{56 + 25}{35} \) = \( \frac{81}{35} \) = 2\(\frac{11}{35}\)
What is the distance in miles of a trip that takes 7 hours at an average speed of 55 miles per hour?
| 75 miles | |
| 150 miles | |
| 225 miles | |
| 385 miles |
Average speed in miles per hour is the number of miles traveled divided by the number of hours:
speed = \( \frac{\text{distance}}{\text{time}} \)Solving for distance:
distance = \( \text{speed} \times \text{time} \)
distance = \( 55mph \times 7h \)
385 miles
A tiger in a zoo has consumed 16 pounds of food in 2 days. If the tiger continues to eat at the same rate, in how many more days will its total food consumtion be 72 pounds?
| 8 | |
| 7 | |
| 6 | |
| 5 |
If the tiger has consumed 16 pounds of food in 2 days that's \( \frac{16}{2} \) = 8 pounds of food per day. The tiger needs to consume 72 - 16 = 56 more pounds of food to reach 72 pounds total. At 8 pounds of food per day that's \( \frac{56}{8} \) = 7 more days.
The total water usage for a city is 50,000 gallons each day. Of that total, 19% is for personal use and 31% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 6,000 | |
| 9,000 | |
| 7,650 | |
| 7,500 |
31% of the water consumption is industrial use and 19% is personal use so (31% - 19%) = 12% more water is used for industrial purposes. 50,000 gallons are consumed daily so industry consumes \( \frac{12}{100} \) x 50,000 gallons = 6,000 gallons.
A menswear store is having a sale: "Buy one shirt at full price and get another shirt for 5% off." If Ezra buys two shirts, each with a regular price of $21, how much money will he save?
| $5.25 | |
| $6.30 | |
| $1.05 | |
| $2.10 |
By buying two shirts, Ezra will save $21 x \( \frac{5}{100} \) = \( \frac{$21 x 5}{100} \) = \( \frac{$105}{100} \) = $1.05 on the second shirt.