| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 2.59 |
| Score | 0% | 52% |
A circular logo is enlarged to fit the lid of a jar. The new diameter is 40% larger than the original. By what percentage has the area of the logo increased?
| 30% | |
| 37\(\frac{1}{2}\)% | |
| 20% | |
| 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 40% the radius (and, consequently, the total area) increases by \( \frac{40\text{%}}{2} \) = 20%
Which of the following statements about exponents is false?
b1 = 1 |
|
b1 = b |
|
all of these are false |
|
b0 = 1 |
A number with an exponent (be) consists of a base (b) raised to a power (e). The exponent indicates the number of times that the base is multiplied by itself. A base with an exponent of 1 equals the base (b1 = b) and a base with an exponent of 0 equals 1 ( (b0 = 1).
Solve 2 + (4 + 2) ÷ 2 x 4 - 52
| \(\frac{6}{7}\) | |
| \(\frac{1}{2}\) | |
| -11 | |
| 1 |
Use PEMDAS (Parentheses, Exponents, Multipy/Divide, Add/Subtract):
2 + (4 + 2) ÷ 2 x 4 - 52
P: 2 + (6) ÷ 2 x 4 - 52
E: 2 + 6 ÷ 2 x 4 - 25
MD: 2 + \( \frac{6}{2} \) x 4 - 25
MD: 2 + \( \frac{24}{2} \) - 25
AS: \( \frac{4}{2} \) + \( \frac{24}{2} \) - 25
AS: \( \frac{28}{2} \) - 25
AS: \( \frac{28 - 50}{2} \)
\( \frac{-22}{2} \)
-11
What is 7\( \sqrt{8} \) x 5\( \sqrt{2} \)?
| 12\( \sqrt{2} \) | |
| 35\( \sqrt{10} \) | |
| 12\( \sqrt{8} \) | |
| 140 |
To multiply terms with radicals, multiply the coefficients and radicands separately:
7\( \sqrt{8} \) x 5\( \sqrt{2} \)
(7 x 5)\( \sqrt{8 \times 2} \)
35\( \sqrt{16} \)
Now we need to simplify the radical:
35\( \sqrt{16} \)
35\( \sqrt{4^2} \)
(35)(4)
140
Which of these numbers is a factor of 28?
| 16 | |
| 14 | |
| 9 | |
| 12 |
The factors of a number are all positive integers that divide evenly into the number. The factors of 28 are 1, 2, 4, 7, 14, 28.