Many students find word problems difficult. In fact, they are often the easiest problems to solve. An organized approach, and some practice will help you ace them. Here’s an example with a step-by-step approach.
Problem: If John is twice as old as Sally, and their ages total 24, then how old are John and Sally.
Step 1: Identify the things you need to figure out.
1) How old is John?
2) How old is Sally?
Give them names, usually one letter to make equations simple. In this example, use J for John's age and S for Sally's age. Sometimes you will only be asked for one of the two, for example: How old is John? Even when you are asked for only one, always give names to all the unknown quantities.
Step 2: Organize the information you are given to help you solve the problem. Hint: If you are asked to find out two things, or there are two unknowns, you will be given two pieces of information. If you are asked to find out three things, you will be given three pieces of information etc. For this problem the information is:
1) John is twice as old as Sally.
2) John’s and Sally's ages total 24.
Step3: Express each piece of information in terms of the names (letters) you have chosen and try to make the sentences more like mathematics.
1) John’s age (J) is two times Sally’s age (S).
2) John’s age (J) plus Sally’s age (S) is 24.
Step 4: Write equations to express the two sentences in Step 3. If you are unsure about the equations, try the formulas with small numbers. For example, if Sally is 3 then you can calculate that John is 6. How did you do it? You multiplied Sally’s age by 2, so write the equation to show that.
1) J = 2 * S
2) J + S = 24
Step 5: Solve the two equations by substituting 1) into 2). 1) J = 2 * S, so put 2 * S in place of J in equation 2) to get:
2*S + S = 24
3*S = 24
S = 8, so you know S (Sally’s age) is 8.
Step 6: Use the first equation: 1), to find J (John’s age)
J = 2*S and we know S = 8
J = 2 * 8
J = 16
Step 7: Express you answer in a sentence.
John’s age is 16 and Sally’s age is 8.
Step 8: You are finished! Congratulate yourself!! If you need more help, contact me at algebratoo@gmail.com for online help from a professional tutor using live web conferencing from www.Mikogo.com and www.Wiziq.com .
