| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.01 |
| Score | 0% | 60% |
The total water usage for a city is 15,000 gallons each day. Of that total, 27% is for personal use and 43% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 9,300 | |
| 4,000 | |
| 9,000 | |
| 2,400 |
43% of the water consumption is industrial use and 27% is personal use so (43% - 27%) = 16% more water is used for industrial purposes. 15,000 gallons are consumed daily so industry consumes \( \frac{16}{100} \) x 15,000 gallons = 2,400 gallons.
What is \( \frac{9}{8} \) - \( \frac{5}{16} \)?
| \( \frac{2}{16} \) | |
| 2 \( \frac{6}{15} \) | |
| \(\frac{13}{16}\) | |
| \( \frac{6}{10} \) |
To subtract these fractions, first find the lowest common multiple of their denominators. The first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80] and the first few multiples of 16 are [16, 32, 48, 64, 80, 96]. The first few multiples they share are [16, 32, 48, 64, 80] making 16 the smallest multiple 8 and 16 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{9 x 2}{8 x 2} \) - \( \frac{5 x 1}{16 x 1} \)
\( \frac{18}{16} \) - \( \frac{5}{16} \)
Now, because the fractions share a common denominator, you can subtract them:
\( \frac{18 - 5}{16} \) = \( \frac{13}{16} \) = \(\frac{13}{16}\)
Convert 7,546,000 to scientific notation.
| 7.546 x 10-5 | |
| 7.546 x 105 | |
| 7.546 x 106 | |
| 7.546 x 107 |
A number in scientific notation has the format 0.000 x 10exponent. To convert to scientific notation, move the decimal point to the right or the left until the number is a decimal between 1 and 10. The exponent of the 10 is the number of places you moved the decimal point and is positive if you moved the decimal point to the left and negative if you moved it to the right:
7,546,000 in scientific notation is 7.546 x 106
A menswear store is having a sale: "Buy one shirt at full price and get another shirt for 30% off." If Damon buys two shirts, each with a regular price of $12, how much money will he save?
| $3.60 | |
| $2.40 | |
| $1.80 | |
| $3.00 |
By buying two shirts, Damon will save $12 x \( \frac{30}{100} \) = \( \frac{$12 x 30}{100} \) = \( \frac{$360}{100} \) = $3.60 on the second shirt.
If the ratio of home fans to visiting fans in a crowd is 3:1 and all 46,000 seats in a stadium are filled, how many home fans are in attendance?
| 22,000 | |
| 34,500 | |
| 22,667 | |
| 33,750 |
A ratio of 3:1 means that there are 3 home fans for every one visiting fan. So, of every 4 fans, 3 are home fans and \( \frac{3}{4} \) of every fan in the stadium is a home fan:
46,000 fans x \( \frac{3}{4} \) = \( \frac{138000}{4} \) = 34,500 fans.