| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.12 |
| Score | 0% | 62% |
In a class of 27 students, 11 are taking German and 10 are taking Spanish. Of the students studying German or Spanish, 5 are taking both courses. How many students are not enrolled in either course?
| 22 | |
| 19 | |
| 27 | |
| 11 |
The number of students taking German or Spanish is 11 + 10 = 21. Of that group of 21, 5 are taking both languages so they've been counted twice (once in the German group and once in the Spanish group). Subtracting them out leaves 21 - 5 = 16 who are taking at least one language. 27 - 16 = 11 students who are not taking either language.
Which of the following statements about exponents is false?
all of these are false |
|
b0 = 1 |
|
b1 = 1 |
|
b1 = b |
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).
What is 9b2 + b2?
| 8b-2 | |
| 10b-4 | |
| 10b2 | |
| 10b4 |
To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so add the coefficients and retain the base and exponent:
9b2 + 1b2
(9 + 1)b2
10b2
Which of the following is an improper fraction?
\({a \over 5} \) |
|
\(1 {2 \over 5} \) |
|
\({2 \over 5} \) |
|
\({7 \over 5} \) |
A rational number (or fraction) is represented as a ratio between two integers, a and b, and has the form \({a \over b}\) where a is the numerator and b is the denominator. An improper fraction (\({5 \over 3} \)) has a numerator with a greater absolute value than the denominator and can be converted into a mixed number (\(1 {2 \over 3} \)) which has a whole number part and a fractional part.
Convert a-4 to remove the negative exponent.
| \( \frac{1}{a^{-4}} \) | |
| \( \frac{-4}{a} \) | |
| \( \frac{1}{a^4} \) | |
| \( \frac{-1}{a^{-4}} \) |
To convert a negative exponent to a positive exponent, calculate the positive exponent then take the reciprocal.