4 x 7 = 28 - 30 = -2. His change is 2 dollars.
Answer:
Answer options
A. Two cities that are 7.5 cm apart on the map are actually 50 km apart.
D. Two cities that are actually 66 km apart are 9.9 cm apart on the map.
Step-by-step explanation:
Step 1
Indicate the scale as shown;
3 cm : 20 km, meaning 3 cm on the map represents 20 km on the ground
A). what does 7.5 cm represent on the ground
Distance on ground=(7.5×20)/3=50 km
B). what does 4 cm represent on the ground
Distance on ground=(4×20)/3=26.67 km
C). what does 45 km on ground represent on the map
Distance on map=(45×3)/20=6.75 cm
D). what does 66 km on ground represent on the map
Distance on the map=(66×3)/20=9.9 cm
Answer: 4.6 horas.
Step-by-step explanation:
Podemos calcular el tiempo necesario por una llave:
si sabemos que se llena en 8 horas con 4 llaves, entonces una sola llave va a tardar 4 veces 8 horas en llenar el tinaco, es decir, una sola llave tarda:
4*8h = 32 horas
ahora, si usamos 7 llaves, el tiempo necesario va a ser un septimo de eso:
(32 h por llave)/(7 llaves) = 32/7 horas = 4.6 horas.
