| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.87 |
| Score | 0% | 57% |
The total water usage for a city is 45,000 gallons each day. Of that total, 21% is for personal use and 35% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 6,300 | |
| 10,500 | |
| 17,000 | |
| 11,200 |
35% of the water consumption is industrial use and 21% is personal use so (35% - 21%) = 14% more water is used for industrial purposes. 45,000 gallons are consumed daily so industry consumes \( \frac{14}{100} \) x 45,000 gallons = 6,300 gallons.
What is the next number in this sequence: 1, 3, 7, 13, 21, __________ ?
| 31 | |
| 37 | |
| 26 | |
| 36 |
The equation for this sequence is:
an = an-1 + 2(n - 1)
where n is the term's order in the sequence, an is the value of the term, and an-1 is the value of the term before an. This makes the next number:
a6 = a5 + 2(6 - 1)
a6 = 21 + 2(5)
a6 = 31
What is \( \frac{9}{4} \) + \( \frac{6}{8} \)?
| 3 | |
| \( \frac{9}{8} \) | |
| \( \frac{4}{10} \) | |
| \( \frac{5}{8} \) |
To add these fractions, first find the lowest common multiple of their denominators. The first few multiples of 4 are [4, 8, 12, 16, 20, 24, 28, 32, 36, 40] and the first few multiples of 8 are [8, 16, 24, 32, 40, 48, 56, 64, 72, 80]. The first few multiples they share are [8, 16, 24, 32, 40] making 8 the smallest multiple 4 and 8 share.
Next, convert the fractions so each denominator equals the lowest common multiple:
\( \frac{9 x 2}{4 x 2} \) + \( \frac{6 x 1}{8 x 1} \)
\( \frac{18}{8} \) + \( \frac{6}{8} \)
Now, because the fractions share a common denominator, you can add them:
\( \frac{18 + 6}{8} \) = \( \frac{24}{8} \) = 3
If the ratio of home fans to visiting fans in a crowd is 3:1 and all 32,000 seats in a stadium are filled, how many home fans are in attendance?
| 36,000 | |
| 27,200 | |
| 24,000 | |
| 31,500 |
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:
32,000 fans x \( \frac{3}{4} \) = \( \frac{96000}{4} \) = 24,000 fans.
A circular logo is enlarged to fit the lid of a jar. The new diameter is 75% larger than the original. By what percentage has the area of the logo increased?
| 22\(\frac{1}{2}\)% | |
| 30% | |
| 37\(\frac{1}{2}\)% | |
| 20% |
The area of a circle is given by the formula A = πr2 where r is the radius of the circle. The radius of a circle is its diameter divided by two so A = π(\( \frac{d}{2} \))2. If the diameter of the logo increases by 75% the radius (and, consequently, the total area) increases by \( \frac{75\text{%}}{2} \) = 37\(\frac{1}{2}\)%