Answer:
1) $283.50
2) 65.21 meters.
Step-by-step explanation:
Part 1)
We know that a spool of ribbon holds 6.75 meters.
A craft club buys 21 spools.
So, the total length of ribbon bought is:

Each meter costs $2. So, the total cost will be:

Part 2)
A spool holds 6.75 meters.
We bought 21 of them, so that total length we have is 141.75 meters.
The club used 76.54 meters.
So, the amount of ribbon that is left is represented by:

Subtract:

So, 65.21 meters of ribbon will be left.
Answer:
the answer is 675.70 or 4,504.33
Step-by-step explanation:
the right answer is that
The cross product of two vectors gives a third vector

that is orthogonal to the first two.

Normalize this vector by dividing it by its norm:

To get another vector orthogonal to the first two, you can just change the sign and use

.
Of means multiply in math (most of the time).
So multiply.
2/5 x 7/10 = 14/50 divided by 2/2 = 7/25
Answer:
a. P(x>20)=0.19
b. P(x≥6)=0.72
c. P(x≤20)=0.81
d. A and C
Step-by-step explanation:
We know that:
1) the probability that a student makes fewer than 6 mistakes is 0.28

2) The probaiblity that a student makes between 6 to 20 mistakes is 0.53.

We will express the proabilibities in function of the information we have.
a. Probability that a student makes more than 20 mistakes.

b. Probability that the student make 6 or more mistakes

c. Probability that a student makes 20 mistakes at most

d. A and C, because A takes a event of more than 20 mistakes and C takes the event of 20 or less mistakes. Both events cover a probability of 1.