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3 years ago

Casey is six times as old as Ralph. In two years, she will be four times as old as Ralph. How old is each of them now?

Mathematics

1 answer:

lisov135 [29]3 years ago

4 0

Ralph is 3 years old

Casey is 18 years old

Step-by-step explanation:

Let the age of Ralph be x

Then Casey is 6 times as old as Ralph will be 6x

In two years

Ralph =x+2

Casey=6x+2 ⇒ 4(x+2)

Equate the two equations for Casey as

6x+2 = 4x+8

6x-4x=8-2

2x=6

x=6/2= 3

Current age;

Ralph= x= 3 years old

Casey=6x = 6*3= 18 years

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Forming expressions and solving equations;brainly.com/question/1280754

Keywords :six, times, years

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Answer:

A) The expression for the number of bacteria is $P(t) = 400e^{0.7783t}$ .

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Step-by-step explanation:

A) Here we have a problem with differential equations. Recall that we can interpret the rate of change of a magnitude as its derivative. So, as the rate change proportionally to the size of the population, we have

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