Answer:
5.5 seconds
Step-by-step explanation:
The function that gives the height of the object after t seconds falling is:
h = -16t^2 + 484.
To find the time when the object reaches the ground, we just need to use the value of h = 0 in the equation, and then find the value of t:
0 = -16t^2 + 484.
16t^2 = 484
t^2 = 30.25
t = 5.5 seconds
So the object will reach the ground after 5.5 seconds
1510*0.02=$30.20 which is larger than $20.00. 2%= 0.02
Answer:
As she ate 1/10 of cake, we need to know how many cake remains after it, so we can substract:
1 - 1/10 = 10/10 - 1/10 = 9/10
Then, we need to divide the 9/10 into 3 portions:
(9/10) / 3 = 9/30 = 3/10
So we know the fractions would be 3/10 each on this situation..
Answer:
54.2 mph
Step-by-step explanation:
Since the drivers leave at the same time and travel in directions 90° from each other, their separation speed can be found using the Pythagorean theorem. Let c represent Cynthia's average speed. Then (c-10) will represent Tim's average speed. Their combined separation speed is 70 miles per hour, so we can write ...
70² = c² +(c -10)²
4900 = 2c² -20c +100 . . . . eliminate parentheses
c² -10c -2400 = 0 . . . . . . . . divide by 2; put in standard form
(c -5)² -2425 = 0 . . . . . . . . . rearrange to vertex form
c = 5 ±5√97 . . . . . . . . . . . . solve for c, simplify radical
c ≈ 54.244 ≈ 54.2 . . . . . . . use the positive solution
Cynthia's average speed was 54.2 miles per hour.
Answer:
Step-by-step explanation:
given that a laptop company claims up to 11.0 hours of wireless web usage for its newest laptop battery life. However, reviews on this laptop shows many complaints about low battery life. A survey on battery life reported by customers shows that it follows a normal distribution with mean 10.5 hours and standard deviation 27 minutes.
convert into same units into hours.
X is N(10.5, 0.45)
a) the probability that the battery life is at least 11.0 hours

(b) the probability that the battery life is less than 10.0 hours
=
(c) the time of use that is exceeded with probability 0.97
=97th percentile
= 11.844
d) The time of use that is exceeded with probability 0.9 is
is 90th percentile = 10.885