In order to solve this problem, you need to find the scale factor. This is done through cross multiplying proportions. In this instance, you have to cross multiply x/4 by 3.5/7. When you multiply x and 7, you get 7x. When you multiply 3.5 and 4, you get 14. Simplify by isolating the variable, and you get 2.

7 0

4 years ago

A raindrops has a mass of 0.50g. how many moles of water does a raindrop contain

alina1380 [7]

So, here you have to look at the periodic table and see what the molar mass of each molecule composing the water compound $H_2 O$
its two hydrogen atom plus an oxygen molecule, making it about 18g per mol.

That said, looking at the mass, we have to ask ourselves, if a mol of water contains 18g of mass, how many moles do we have in 0.5g of water?
We just do a cross multiplication:
$\frac{(0.5)}{18} =0.027 mol$

7 0

4 years ago

Emilio asked his aunt for $20 to buy supplies for his lemonade stand. Once his stand opened he made $40 a day

FrozenT [24]

The equation that represents profit is $40x - $20.

The profit after 5 days in business is $180.

The profit after 10 days in business is $380.

The profit after 10 days in business if revenue is $45 is $430.

<h3>What is profit? </h3>

Profit is total revenue less total cost.

Profit = total revenue - total cost

Profit = $40x - $20

Where:

x = number of days

<h3>What is the total profit after 5 days and 10 days? </h3>

$40(5) - $20

= $200 - $20

= $180

$40(10) - $20

$400 - $20

$380

<h3>What is total profit if revenue is $45? </h3>

$45(10) - $20

= $450 - $20

= $430

To learn more about profit, please check: brainly.com/question/26181966

8 0

3 years ago