Answer:
Juan imprimió 7 páginas a color.
Step-by-step explanation:
Llamemos "b" a las copias en blanco y negro y "c" a las copias en color.
Juan imprimió 75 páginas. En forma simbólica es:
b + c = 75
b = 75 - c [1]
El costo de impresión de cada página en una biblioteca es de 5 centavos si es en blanco y negro o 50 centavos si es a color. En total pago $6.90. En forma simbólica es:
0.05b + 0.5c = 6.90 [2]
Si reemplazamos [1] en [2],
0.05(75-c) + 0.5c = 6.90
3.75 - 0.05c + 0.5c = 6.90
0.45c = 3.15
c = 7
Juan imprimió 7 páginas a color.
Answer:
It's a valid sample because the first five people were selected to participate.
Step-by-step explanation:
True because random people who saw the advertisement responded. By chance, not every person who saw the advertisement answered, therefore it was random, but it would be more random if he decided to reject the second, fourth, sixth, and eighth person, and only the first, third, fifth, seventh, and ninth were chosen.
I am pretty sure it depends on what your numbers are
Bring y to one side and the rest to the other switching the positives to negative then you’ll get Y=114
44%
42%
78%
21%
30%
8%
i calculated everything