84 ÷ 2 = 42
Check it to make sure.
2 × 42 = 84
42 and 2 can be multiplied to get 84.
Answer:
-1.683
Step-by-step explanation:
Given :
Group 1 :
x1 = 667 ; n1 = 10 ; s1 = 20
Group 2 :
x2 = 679 ; n2 = 14 ; s2 = 15
The test statistic assuming equal variance :
x1 - x2 / √[Sp² * (1/n1 + 1/n2)]
sp² = [(n1 - 1)*s1² + (n2 - 1)*s2²] ÷ (n1 + n2 - 2)
Sp² = [(10 - 1)*20² + (14 - 1)*15²] = 296.59
Test statistic =
(667 - 679)/ √[296.59 * (1/10 + 1/14)]
-12 / 7.1304978
Test statistic = - 1.682
Answer:
by factoring the answer is - x=1/2, 5
Step-by-step explanation:
hope it helps:))
Answer:
see explanation
Step-by-step explanation:
the perimeter (P) is the sum of the 4 sides
(a)
P = a + b + c + d
= x + 7 + 2x + 2 + 8x + x + 10 ← collect like terms
= 12x + 19
(b)
If x = 4 , then
P = 12x + 19 = 12(4) + 19 = 48 + 19 = 67
(c)
If x = 2 , then
P = 12x + 19 = 12(2) + 19 = 24 + 19 = 43
(d)
P = a + b + c + d
= x² + 4x + 8 + 2x² + x ← collect like terms
= 3x² + 5x + 8
7th grade has 3 boy out of 10 students
probability of picking a boy is 3/10
8th grade has 9 boys out of 12 students are boys
probability of picking a boy is 9/12 reduced to 3/4
3/10 x 3/4 = 9/40 probability of picking 2 boys