Answer:
what is the question
Step-by-step explanation:
Define
g = 9.8 32.2 ft/s², the acceleration due to gravity.
Refer to the diagram shown below.
The initial height at 123 feet above ground is the reference position. Therefore the ground is at a height of - 123 ft, measured upward.
Because the initial upward velocity is - 11 ft/s, the height at time t seconds is
h(t) = -11t - (1/2)gt²
or
h(t) = -11t - 16.1t²
When the ball hits the ground, h = -123.
Therefore
-11t - 16.1t² = -123
11t + 16.1t² = 123
16.1t² + 11t - 123 = 0
t² + 0.6832t - 7.64 = 0
Solve with the quadratic formula.
t = (1/2) [-0.6832 +/- √(0.4668 + 30.56) ] = 2.4435 or -3.1267 s
Reject the negative answer.
The ball strikes the ground after 2.44 seconds.
Answer: 2.44 s
Parenthesis
Exponent
Multiplication
Division
Addition
Subtraction
(left to right)
4²-(3.1+6.4)+4.5
According to PEMDAS, we will do what is inside the parenthesis.
3.1+6.4 = 9.5
<em>4²-9.5+4.5</em>
Then we do figure out the exponent.
4² = (4)(4) = 16
<em>16-9.5+4.5</em>
Then we do subtraction then addition because PEMDAS also tells us we should do adding and subtracting from left to right. In this expression, subtracting is on the left side so we should do that first.
16-9.5 = 6.5
<em>6.5 + 4.5 = 11</em>
11 is your answer :)
Answer: The probability of drawing a red marble the sixth time is 1/2
Step-by-step explanation:
Here is the complete question:
A box contains 10 red marbles and 10 green marbles. Sampling at random from the box five times with replacement, you have drawn a red marble all five times. What is the probability of drawing a red marble the sixth time?
Explanation:
Since the sampling at random from the box containing the marbles is with replacement, that is, after picking a marble, it is replaced before picking another one, the probability of picking a red marble is the same for each sampling. Probability, P(A) is given by the ratio of the number of favourable outcome to the total number of favourable outcome.
From the question,
Number of favourable outcome = number of red marbles =10
Total number of favourable outcome = total number of marbles = 10+10= 20
Hence, probability of drawing a red marble P(R) = 10 ÷ 20
P(R) = 1/2
Since the probability of picking a red marble is the same for each sampling, the probability of picking a red marble the sixth time is 1/2