Answer:
9
Step-by-step explanation:
first, turn both fractions into improper
turn it into multiplication
simplify
A normal distribution is symmetrical about the mean. Therefore half of all young men are shorter than 68 inches.
Answer:
(-3, 0)
Step-by-step explanation:
Let's solve this system using the elimination by addition/subtraction method. Begin by writing the two equations one above the other:
5x +2y =-15
2x - 2y =-6
Notice that the y terms cancel each other out:
5x +2y =-15
2x - 2y =-6
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7x = -21
Dividing both sides by 7 results in x = -3.
Subbing -3 for x in either of the given equations leads to finding y:
5(-3) + 2y = -15, or -15 + 2y = -15. This results in 2y = 0, or y = 0.
The solution is (-3, 0).
Answer:
y = 30
Step-by-step explanation:
Use the direct variation equation, y = kx
Plug in 20 as y and 8 as x, then solve for k:
y = kx
20 = k(8)
2.5 = k
So, the equation is y = 2.5x
Plug in 12 as x, and solve for y:
y = 2.5x
y = 2.5(12)
y = 30
So, when x = 12, y = 30
a. Notice that
1/(1*2) = 1/2 = 1 - 1/2
1/(2*3) = 1/6 = 1/2 - 1/3
1/(3*4) = 1/12 = 1/3 - 1/4
and so on, which suggests the n-th term of the sum can be written as
Then the sum itself is telescoping:
b. The proof is trivial:
so the formula found in (a) is correct.
