Answer:
20%
Step-by-step explanation:
$(200 000/ 250 000) = .8 = 80%, seguís pagando 80% entonces distes un descuento de 20% (100-80=20%)
Answer:
$8.85
Step-by-step explanation:
This a question of direct variation, so we can make out a relationship between the two factors. 12 is 2/3 of 18, so the cost of 12 would also be 2/3 of the cost of 18. We can now make an equation to solve.

Answer:
4
Step-by-step explanation:
If the slope is 0, the line is horizontal and the y-coordinate is 4 for all x values.
Thus the missing y-coordinate is 4.
Suppose

is the number of possible combinations for a suitcase with a lock consisting of

wheels. If you added one more wheel onto the lock, there would only be 9 allowed possible digits you can use for the new wheel. This means the number of possible combinations for

wheels, or

is given recursively by the formula

starting with

(because you can start the combination with any one of the ten available digits 0 through 9).
For example, if the combination for a 3-wheel lock is 282, then a 4-wheel lock can be any one of 2820, 2821, 2823, ..., 2829 (nine possibilities depending on the second-to-last digit).
By substitution, you have

This means a lock with 55 wheels will have

possible combinations (a number with 53 digits).