Answer:
127.5
Step-by-step explanation:
The given series is 26 + 24.5 + 23 + 21.5 + ... - 17.5
The first term of this series is a=26
The common difference is d=24.5-26=-1.5
The last term of the series is -17.5
The nth term is given by:
n=30
The sum of the series:
Answer:
D. 76
Step-by-step explanation:
because students that has 5 absences and less most likely to get higher than 75 marks. The student who has 8 absences studied at home, he's a genius
Answer:
F. 8
Step-by-step explanation:
The ratio of the long side to the short side is the same in similar triangles. The long side of triangle BAD is AD, which has length 20-4 = 16.
BD/DE = AD/BD
h/4 = 16/h
h^2 = 64 . . . . . . . multiply by 4h
h = 8 . . . . . . . . . . take the square root (matches selection F)
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<em>Comment on this geometry</em>
BD = √(AD·DC) is called the "geometric mean" of the segments AD and DC. This geometry has some other geometric mean relationships as well:
BC = √(AC·DC)
BA = √(AC·AD)
