Introduction to percent word problem solving:
In math, percent is an expression, expressing the fraction as a percent (that is "per" "cent" means "per" "hundred"). The percentage is represented as "%" sign. The percentage of the number is expressed as 7%. Percentage expresses whether one quantity is larger or smaller with respect to the other quantity. The word problem is expressed in which it fits the equation.
There are three steps to solving math word problems:
Translate into equations
Solve the equations and
Check the answer
In math percent word problems, we have to translate the simple English statements into mathematical expressions. For example “of” indicates multiplication (times). Percentage word problems can be easily solved by using the rule, If suppose,
"(x) is (some percentage) of (y)", which translates to "(x) = (some decimal) × (y)"
Formula for Percent Word Problem Solving:
Formula for percentage:
The formula for percentage is the following and it must be easy to use:
`"is"/"of" = "%"/"100"`
Example 1:
What percent of 40 is 50?
Solution:
The given statement is
Percent * 40 = 50
Therefore,
x % `xx` 40 = 50
`x/100` `xx` 40 = 50
`(40x)/100` = 50
Now cross multiply to get
40x = 50*100 = 5000
x = `5000/40`
x = 125
Therefore, Fifty is 125% of 40
Example 2:
25% of what is 30?
Solution:
The statement is
25% `xx` x = 30
Therefore,
`25/100` `xx` x = 30
`(25x)/100" ` = 30
x = `3000/25`
= 120
Answer: 30 is 25% of 120
Examples of Percent Word Problem Solving:
Example 3:
In a college, 30% of students are studying computer science. If their total number is 120, how many students are studying in that college totally?
Solution:
There are 30% of students are studing computer science. We understood that 30% of all students in college are equal to number of students studying computer science.
Therefore, the equation is
30% of x = 120
`30/100`` xx x` = 120
30 x = 120 * 100
30 x = 12000
x = 12000/30
x = 400
Therefore, we have 400 students in the college.
Practice Percentage Word Problems
Practice problem 1:
What percent of 15 is 20?
Answer key: 133.33
Practice problem 2:
40% of what is 70?
Answer key: 175
Practice problem 3:
In a test there are 30 questions in total. If john gets 70% correct, how many questions did john missed?
Answer key: John missed 9 questions
In math, percent is an expression, expressing the fraction as a percent (that is "per" "cent" means "per" "hundred"). The percentage is represented as "%" sign. The percentage of the number is expressed as 7%. Percentage expresses whether one quantity is larger or smaller with respect to the other quantity. The word problem is expressed in which it fits the equation.
There are three steps to solving math word problems:
Translate into equations
Solve the equations and
Check the answer
In math percent word problems, we have to translate the simple English statements into mathematical expressions. For example “of” indicates multiplication (times). Percentage word problems can be easily solved by using the rule, If suppose,
"(x) is (some percentage) of (y)", which translates to "(x) = (some decimal) × (y)"
Formula for Percent Word Problem Solving:
Formula for percentage:
The formula for percentage is the following and it must be easy to use:
`"is"/"of" = "%"/"100"`
Example 1:
What percent of 40 is 50?
Solution:
The given statement is
Percent * 40 = 50
Therefore,
x % `xx` 40 = 50
`x/100` `xx` 40 = 50
`(40x)/100` = 50
Now cross multiply to get
40x = 50*100 = 5000
x = `5000/40`
x = 125
Therefore, Fifty is 125% of 40
Example 2:
25% of what is 30?
Solution:
The statement is
25% `xx` x = 30
Therefore,
`25/100` `xx` x = 30
`(25x)/100" ` = 30
x = `3000/25`
= 120
Answer: 30 is 25% of 120
Examples of Percent Word Problem Solving:
Example 3:
In a college, 30% of students are studying computer science. If their total number is 120, how many students are studying in that college totally?
Solution:
There are 30% of students are studing computer science. We understood that 30% of all students in college are equal to number of students studying computer science.
Therefore, the equation is
30% of x = 120
`30/100`` xx x` = 120
30 x = 120 * 100
30 x = 12000
x = 12000/30
x = 400
Therefore, we have 400 students in the college.
Practice Percentage Word Problems
Practice problem 1:
What percent of 15 is 20?
Answer key: 133.33
Practice problem 2:
40% of what is 70?
Answer key: 175
Practice problem 3:
In a test there are 30 questions in total. If john gets 70% correct, how many questions did john missed?
Answer key: John missed 9 questions
No comments:
Post a Comment