45. Find your percent correct on a test if you received 61 points out of 69 possible.

88.4%

49. Find your percent on a test if you received 42 points out of 80 possible.

52.5%

50. Scientific notation is most effective when used with _____
a. very small numbers
b. very large numbers
c. imaginary numbers
d. very large and very small numbers

D

45 and 49 are correct.

No idea about the last one.

The last one is correct, as well.

To find the percent correct on a test, divide the number of points earned by the total possible points and then multiply by 100.

For the first question:
Points earned = 61
Total possible points = 69

Percent correct = (61/69) * 100
Percent correct = 0.884 * 100
Percent correct = 88.4%

For the second question:
Points earned = 42
Total possible points = 80

Percent correct = (42/80) * 100
Percent correct = 0.525 * 100
Percent correct = 52.5%

To answer the third question about scientific notation, the most effective use of scientific notation is for representing very large and very small numbers. Therefore, the answer is option d.