Answer:
96
Step-by-step explanation:
commom difference = d
a₆ + a₇ = 16
a₅ + a₈ = (a₆ - d) + (a₇ + d) = a₆ + a₇ = 16
a₄ + a₉ = (a₆ - 2d) + (a₇ + 2d) = a₆ + a₇ = 16
Similarly,
a₃ + a₁₀ = 16, a₂ + a₁₁ = 16, a₁ + a₁₂ = 16
so
a₁ + a₂ + ... + a₁₁ + a₁₂ = 6 x 16 = 96
Answer:
240
Step-by-step explanation:
If you draw a straight line, 12 would meet at 240. Hope this is helpful! You were close but I think you mixed up 240 and 300.
Answer:
Probability that average height would be shorter than 63 inches = 0.30854 .
Step-by-step explanation:
We are given that the average height of 20-year-old American women is normally distributed with a mean of 64 inches and standard deviation of 4 inches.
Also, a random sample of 4 women from this population is taken and their average height is computed.
Let X bar = Average height
The z score probability distribution for average height is given by;
Z =
~ N(0,1)
where,
= population mean = 64 inches
= standard deviation = 4 inches
n = sample of women = 4
So, Probability that average height would be shorter than 63 inches is given by = P(X bar < 63 inches)
P(X bar < 63) = P(
<
) = P(Z < -0.5) = 1 - P(Z <= 0.5)
= 1 - 0.69146 = 0.30854
Hence, it is 30.85% likely that average height would be shorter than 63 inches.
Notice that a can is a cylinder, which is basically two circles and one rectangle. Now, the question wants area of this rectangle.
You know the width of the rectangle (or the paper), which is 11cm. How do you find the length then?
Notice that the length of the rectangle is also the circumference of the circles. From here, use C = πd where C is circumference and d is diameter. The d is given, which is 7.5 cm. Depending on the question, π can be 3.14, 22/7 or the actual pi.
multiply π and 7.5cm and you get the circumference. Multiply this to 11cm and you get area of the rectangle.