41.3 is the answer to this question
Answer:
Muchos de los problemas de las ciencias, economía, finanzas, medicina y otros numerosos campos se pueden traducir a problemas de álgebra. Ésta es una razón por la
que el álgebra es tan útil. En esta sección usamos las ecuaciones como modelos
matemáticos para resolver problemas de la vida cotidiana.
Criterios para modelar con ecuaciones
Se aplican los siguientes criterios para plantear ecuaciones que modelen situaciones
formuladas en palabras. Para mostrar la manera en que los criterios pueden ayudar a
plantear las ecuaciones, anotamos al margen cuándo funciona cada ejemplo de esta
sección
Step-by-step explanation:
Answer:
x = 13
Step-by-step explanation:
Since the triangles are similar then the ratios of corresponding sides are equal, that is
=
, substitute values
=
( cross- multiply )
78(11x - 13) = 10140 ( divide both sides by 78 )
11x - 13 = 130 ( add 13 to both sides )
11x = 143 ( divide both sides by 11 )
x = 13
Answer:
At least 6907 people.
Step-by-step explanation:
Population std deviation = sigma= 10.6
Since population std deviation is known, we can use normal probability table to get sample size from confidence interval.
The sample mean weight loss is within 0.25 lb of the true population mean.
Hence margin of error < 0.25
Margin of error = z critical (std dev/n) where n = sample size
Z critical for 95% = 1.96
Hence 0.25 >1.96(10.6)/sq rt n
Simplify to get
sq rt n > 1.96(10.6)/0.25 = 83.104
Square both the sides to get
n > 83.104 square = 6906.27
i.e. sample size should be atleast 6907.
Answer:
x = 5.7 years after 2000
Step-by-step explanation:
So the year when both the amount of users were the same can be found by using the both equations to solve for x (since y is the same)
48x + y = 729
we will take the value of y from this equation and use it in the other equation
y = 729 - 48x
135x - 2y = -140
135x - 2(729 - 48x) = -140
135x -1458 + 98x = -140
231x = 1318
x = 1318/231
x = 5.7 years after 2000