There will only be one solution to this problem.
220 = 2x - 12x
Combine like terms on the right side of the equation:
220 = - 10x
Divide both sides by - 10 to isolate the variable x.
220 / - 10 = x
-22 = x, one solution.
20 km
12.5 miles = (12.5*8)/5 = 20 km
hope it helps you!!!!!!!!!!
You got the first part right
The theoretical probability is related to 1/2. A coin toss should always come up heads 1/2 the time and tails one 1/2 the time. So out of a class of 40 people, 20 people should flip (say) heads in theory and the other half of a class of 40 should flip tails 20 times.
Put more formally it looks like this.
P(sample) = Sample size * P(of it occurring once)
P(of it occurring once) = 1/2
Sample size = 40
P(sample) = 40 * 1/2
P(sample) = 20