| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.86 |
| Score | 0% | 57% |
A circular logo is enlarged to fit the lid of a jar. The new diameter is 45% larger than the original. By what percentage has the area of the logo increased?
| 27\(\frac{1}{2}\)% | |
| 22\(\frac{1}{2}\)% | |
| 30% | |
| 25% |
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 45% the radius (and, consequently, the total area) increases by \( \frac{45\text{%}}{2} \) = 22\(\frac{1}{2}\)%
Which of these numbers is a factor of 64?
| 4 | |
| 7 | |
| 61 | |
| 5 |
The factors of a number are all positive integers that divide evenly into the number. The factors of 64 are 1, 2, 4, 8, 16, 32, 64.
A tiger in a zoo has consumed 33 pounds of food in 3 days. If the tiger continues to eat at the same rate, in how many more days will its total food consumtion be 110 pounds?
| 7 | |
| 9 | |
| 3 | |
| 4 |
If the tiger has consumed 33 pounds of food in 3 days that's \( \frac{33}{3} \) = 11 pounds of food per day. The tiger needs to consume 110 - 33 = 77 more pounds of food to reach 110 pounds total. At 11 pounds of food per day that's \( \frac{77}{11} \) = 7 more days.
What is \( 4 \)\( \sqrt{45} \) + \( 8 \)\( \sqrt{5} \)
| 12\( \sqrt{225} \) | |
| 20\( \sqrt{5} \) | |
| 32\( \sqrt{225} \) | |
| 32\( \sqrt{5} \) |
To add these radicals together their radicands must be the same:
4\( \sqrt{45} \) + 8\( \sqrt{5} \)
4\( \sqrt{9 \times 5} \) + 8\( \sqrt{5} \)
4\( \sqrt{3^2 \times 5} \) + 8\( \sqrt{5} \)
(4)(3)\( \sqrt{5} \) + 8\( \sqrt{5} \)
12\( \sqrt{5} \) + 8\( \sqrt{5} \)
Now that the radicands are identical, you can add them together:
12\( \sqrt{5} \) + 8\( \sqrt{5} \)What is -5z7 x 9z3?
| 4z10 | |
| -45z-4 | |
| -45z10 | |
| -45z4 |
To multiply terms with exponents, the base of both exponents must be the same. In this case they are so multiply the coefficients and add the exponents:
-5z7 x 9z3
(-5 x 9)z(7 + 3)
-45z10