Answer: r = 7
Step-by-step explanation:
Subtract 12 from both sides to isolate the r variable. You have -42 = -6r. Divide both sides by -6 to get r by itself and you get r = 7. Verify by substituting 7 as the r value and solving the equation.
Combinations of 7 taken 4 at a time.
C (7,4) = 7! /[ 4!(3!)]
7 x 6 x 5 = 210
210 divided by 3 = 70
70 divided by 2 = 35
Answer:
5C
6C
7D
8B
Step-by-step explanation:
5) C because median is the middle of the set of numbers source A median is 4 source B median is 6 and 4 is 2 less than 6.
6) C because there are 6 numbers altogether and 1 6s on a dice so 6+6 because we have two dice and 2 6s on both so 2/12 or simplified 1/6
7) D because mean is all the numbers add up divided by the amount of numbers so 20+25+30+20+30 = 125 and 125 ÷ 5 = 25
8 B because mean is all the numbers add up divided by the amount of numbers so
5+6+7+8+8+8+8+8+8+9+9 = 76 ÷ by 10 is 7.6
7+7+7+7+8+8+8+8+10+10 = 80 ÷ by 10 = 8
8 + 7.6 = 15.6 ÷ 2 = 7.8 and B is closest to 7.8
Answer:
Number of children = 386
Number of adults = 287
Step-by-step explanation:
Let
x = number of children
y = number of adults
x + y = 673 (1)
1.75x + 2y = 1249.50 (2)
From (1)
x = 673 - y
Substitute x = 673 - y into (2)
1.75x + 2y = 1249.50
1.75(673 - y) + 2y = 1249.50
1177.75 - 1.75y + 2y = 1249.50
- 1.75y + 2y = 1249.50 - 1177.75
0.25y = 71.75
y = 71.75/0.25
y = 287
Substitute y = 287 into (1)
x + y = 673
x + 287 = 673
x = 673 - 287
x = 386
Number of children = 386
Number of adults = 287