|<br> Evaluate 5c + cd when c<br> --<br> and d = 15.

Research scientists need a certain type of bacteria to conduct an experiment. There are 2,500 bacteria in a certain culture. The

pychu [463]

Answer:

7 days

Step-by-step explanation:

At 25% per day, it will take approximately 3 days to double the population, so approximately 6 days for the population to quadruple. Checking that number, we find it is not quite enough for the experiment, so another day is required.

"Guess and check" as a method of solution works especially well if you have an automated checker to evaluate your guess. A graphing calculator or spreadsheet can work well for this.

_____

We guess 3 days as the doubling time using the "rule of 72" that says the product of percentage and doubling time is about 72. That is, 72/25 ≈ 3. (This is only a very rough approximation of doubling time, best for rates near 8%.)

7 0

3 years ago

I need help i will give the brainleness thing to whoever can answer

dimaraw [331]

Answer:

A=30cm, B=39cm

Step-by-step explanation:

They are an enlargement. Therefore, the sides are larger by the same proportion, otherwise, it wouldn't be an enlargement. Therefore, the bottom side of the big one is 3 times that of the small one. Therefore, the other sides are also 3 times, making A = 30cm and B = 39cm.

8 0

3 years ago

Read 2 more answers

Steve earns $8 per hour. His older brother earns $2 more per hour than Steve. What is the ratio of the money Steve earns in an h

Licemer1 [7]

Answer: 4:5

Explanation:

Steve earns 8 dollars an hour. His brother earns 10 dollars an hour.

The ratio is Steve:Brother, which is 8:10.

This can be treated the same was as a fraction and simplified, dividing both sides by 2, which becomes 4:5

5 0

3 years ago

Is these two correct?<br> Just to make sure.

Ymorist [56]

Answer:

It should be correct

Step-by-step explanation:

6 0

4 years ago

Read 2 more answers

Callie has 2 cans of orange paint with 4.5 gallons in each can. She also has 910 of a gallon of black paint. Her brother took 0.

Solnce55 [7]

Answer:

The total amount of paint left is 1.6 gallon of paint remaining

Where she has:

1.5 gallon of orange paint left and 0.1 gallon of black paint left.

Step-by-step explanation:

Step 1

Callie has 2 cans of orange paint with 4.5 gallons in each can.

The total gallons of orange paint that she has is given as:

1 can = 4.5 gallons

2 cans = x gallons

Cross Multiply

x = 4.5 gallons × 2 cans

x = 9 gallons of orange paint.

She also has 9/10 of a gallon of black paint.

Her brother took 0.8 gallon of the black paint

and 3.75 gallons from each of the cans of orange paint.

Since there are 2 cans, the total gallons of orange paint that her brother took = 2 × 3.75 gallons

= 7.5 gallons

Step 2

For orange paint

The amount of orange paint that she has left = 9 gallons - 7.5 gallons

= 1.5 gallons of orange paint left.

For black paint

We are told that: She also has 9/10 of a gallon of black paint.

Converting to decimal

= 0.9 gallon of black paint.

Her brother took 0.8 gallon of the black paint

The total gallon of black paint that she has left =

0.9 gallon - 0.8 gallon

= 0.1 gallon of black paint left.

The total amount of paint Callie has remaining after her brother took the stated amounts is:

1.5 gallon of orange paint + 0.1 gallon of black paint = 1.6 gallon of paint remaining

4 0

3 years ago

| Evaluate 5c + cd when c -- and d = 15.