We know P = 1/2
X~B(2, 0.5)
n = 1
2C1 from pascal triangle = 2
P(X=0.5)= 2C1 x 0.5 x 0.5
= 0.5
= 50%
Answer: C
Explanation: We need to combine like terms, which means 7a and -12a and -8 and 4
7-12=5 and -8+4=-4
Steve ran 11 miles
let the distance Steve ran be x
Then distance Kevin ran is x + 4 ( 4 miles more than Steve )
x + x + 4 = 26 ( the sum of their distance is 26 )
2x + 4 = 26 ( subtract 4 from both sides )
2x = 22 ( divide both sides by 2 )
x = 11
Steve ran 11 mies and Kevin ran 11 + 4 = 15 miles
check 11 + 15 = 26