If the mean score is 55% and the s.d. is 15%, then a test score of at least
55% + 1.5 × 15% = 77.5%
falls in the A range.
The next cutoff score is 0.5 s.d. from the mean, which is
55% + 0.5 × 15% = 62.5%
so any test score between 62.5% and 77.5% is in the B range.
The next cutoff is
55% - 0.5 × 15% = 47.5%
so a score between 47.5% and 62.5% gets a C.
The lower limit of the next range is
55% - 1.5 × 15% = 32.5%
so 32.5% - 47.5% gets a D.
Anything lower than 32.5% is an F.
0.91÷-0.13
=-7
hope this helps!
Answer:
64
Step-by-step explanation:
1
2
3
4
1, 2
1, 3
1, 4
2, 1
2, 3
2, 4
3, 1
3, 2
3, 4
4, 1
4, 2
4, 3
1, 2, 3
1, 2, 4
1, 3, 2
1, 3, 4
1, 4, 2
1, 4, 3
2, 1, 3
2, 1, 4
2, 3, 1
2, 3, 4
2, 4, 1
2, 4, 3
3, 1, 2
3, 1, 4
3, 2, 1
3, 2, 4
3, 4, 1
3, 4, 2
4, 1, 2
4, 1, 3
4, 2, 1
4, 2, 3
4, 3, 1
4, 3, 2
1, 2, 3, 4
1, 2, 4, 3
1, 3, 2, 4
1, 3, 4, 2
1, 4, 2, 3
1, 4, 3, 2
2, 1, 3, 4
2, 1, 4, 3
2, 3, 1, 4
2, 3, 4, 1
2, 4, 1, 3
2, 4, 3, 1
3, 1, 2, 4
3, 1, 4, 2
3, 2, 1, 4
3, 2, 4, 1
3, 4, 1, 2
3, 4, 2, 1
4, 1, 2, 3
4, 1, 3, 2
4, 2, 1, 3
4, 2, 3, 1
4, 3, 1, 2
4, 3, 2, 1
Answer:
3x and 2x can be combined bc it has ex at the end.
1 and 2x cannot be combined bc 1 doesn't have an x.
1 and -5 can be combined
