5 minutes
100 sit-ups in 2 minutes means 50 sit-ups per minute
amount of sit-ups / mins
100 / 2
200. /. 4
300. /. 6
51X2=102
51 goes into 102 evenly twice
You have the equations set up correctly. I will use r and b as the variables to make it easier to follow.
12r + 8b = 70
20r + 12b = 110
First let's solve one of the equations for one of the variables.
12r = 70 - 8b

Now plug that in for r in the second equation.

Simplify



b = 5 grams
Now plug 5 in for b in one of the original equations to find r.
12r + 8(5) = 70
12r = 30
r = 2.5 grams
So the red marbles weigh 2.5 grams, and the blue marbles weigh 5 grams.
Box and whiskers plots use five number summaries. The first number is:
1:Minimum
2.Quartile 1
3.Mean
4.Quartile 2
5.maximum
Quartile are simple to get.
If your set of numbers is:
2,3,3,6,8,8,11
Then find the mean
2 3 3 |6| 8 8 11
Find the mean of the left side of of mean.
2 |3| 3 3 =Quartile 1
Then the right side
8 |8| 11 8 =Quartile 2
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Your 5 number summary is 2,3,6,8,11
Plot them on the number line, but put a line above where the dot would go. take the 3 middle lines and connect to make a box. The lines on the outside of the box are the whiskers, AKA distributed data.
Multiply 4 on both sides.
x = 8 / 5
x = 1 3/5
Hope this helps!