Isoceles triangles have one pair of congruent base angles opposite their congruent sides. Also, the angles in a triangle add up to 180°. Therefore, we can set up this equation:
100 + x + x = 180
(we know it's not the 100° angle that has a congruent match because that would cause the total angle measure to go above 180°)
100 + 2x = 180
Subtract 100 from each side.
2x = 80
Divide by 2.
x = 40°
Both of the other angles would be 40°.
1 $ = 100 cents
1.5 $ = 150 cents
1.50 $ a percentage of 200 cents = (150/200)100= 75%
(a) The probability that there is no open route from A to B is (0.2)^3 = 0.008.
Therefore the probability that at least one route is open from A to B is given by: 1 - 0.008 = 0.992.
The probability that there is no open route from B to C is (0.2)^2 = 0.04.
Therefore the probability that at least one route is open from B to C is given by:
1 - 0.04 = 0.96.
The probability that at least one route is open from A to C is:

(b)
α The probability that at least one route is open from A to B would become 0.9984. The probability in (a) will become:

β The probability that at least one route is open from B to C would become 0.992. The probability in (a) will become:

Gamma: The probability that a highway between A and C will not be blocked in rush hour is 0.8. We need to find the probability that there is at least one route open from A to C using either a route A to B to C, or the route A to C direct. This is found by using the formula:


Therefore building a highway direct from A to C gives the highest probability that there is at least one route open from A to C.