This problem can be solved by using the rules of system of equations. You have two situations: 1) when 3 vans and 1 car can transport 22 student; 2) when 2 vans and 4 cars can transport 28 students. Let's name students in the van
V; students in the car - C. Now think this way: in first...

Think this way: total amount of question is 25 and it is 100%. Right a proportion: if 25 is 100%, then 23 - X%
25 =
23
100 = X
Cross multiply and you will have:
25x = 2300
Divide both parts of equation by 25.
The answer is 92%.

A molecule is formed when two or more atoms join together chemically.
A compound is a molecule that contains at least two different elements. All compounds are molecules but not all molecules are compounds.
Molecular hydrogen (H2), molecular oxygen (O2) and molecular nitrogen (N2) are not...

The mass number corresponds to the mass of the atom, that is obtained by adding the number of protons and neutrons present.
The mass numbers appears under the element symbol in the elements table. For instance, the atomic mass of oxygen is = 16. For nitrogen = 14.
Atomic...