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3 years ago

122 cats

Mathematics

1 answer:

pshichka [43]3 years ago

8 0

Answer:

Step-by-step explanation:

To find how old Mrs. Roberts was when her son was born, we first need to know both of their ages. I'm going to give Mrs. Roberts the variable m and her son the variable s.

Let's turn the two sentences about their ages into equations:

m=Mrs. Roberts and 3s= three times as old as her son

m=3s

m+s is the sum of their ages

m+s=48

Now substitute the first equation into the second one:

m+s=48

(3s)+s=48

4s=48

s=12

The son is 12 years old. Now substitute s into one of the equations to solve for the mother's age:

m=3s

m=3(12)

m=36

Mrs. Roberts is 36. Since they are asking how old she was when her son was born, we will subtract her son's age from her age, since she would be 12 years younger:

36−12=24

Mrs. Roberts was 24 when her son was born.

credit to CountryGirl on Socratic Q&A

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Step-by-step explanation:

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3 years ago

How many times larger is 9 x 10-8 than 3 x 10-12?

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9x10-8 is about 4.5 times larger than 3x10-12

First solve the equations

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3 years ago

A rental car company charges $53.75 per day to rent a car and $0.12 for every mile driven. Jaya wants to rent a car, knowing tha

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Jaya can afford to rent a car 4 days while staying within her budget.

Step-by-step explanation:

The inequality would have to indicate that the cost of renting a car has to be less than or equal to $230. The cost to rent a car is equal to the cost per day for the number of days plus the price per mile for the number of miles, which is:

53.75x+0.12y≤230, where:

x is the number of days the car is rented

y is the number of miles driven

As the statement says that she plans to drive 125 miles, you can replace "y" with this value and solve for x:

53.75x+0.12(125)≤230

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53.75x≤230-15

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According to this, the answer is that Jaya can afford to rent a car 4 days while staying within her budget.

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3 years ago

Safety regulations require that the time between airplane takeoffs (on the same runway) will be at least 2 minutes. When taking

Xelga [282]

Answer:

1 plane

Step-by-step explanation:

Let's suppose the number of planes waiting or on the runway " P "

the number of planes taking off per hour ' $P_{takeoff}$ '

the time for waiting and the runway $T_{wr}$ so:

P = $P_{takeoff}$ x $T_{wr}$

$P_{takeoff}$ = 18 airplanes per hour

we know that 1 min = 60s

36s = 36/60 = 0.6 min

Also, 3 min and 30 s = 3 + 30/60 = 3.5 min

Next to find the time for waiting and the runway

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$T_{wr}$ = 0.068 hour

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So, there is 1 plane either on the runway or waiting to take off

Read more on Brainly.com - brainly.com/question/13622877#readmore

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3 years ago