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3 votes
1/4 of a certain number is removed from two fifth of that number if the result is 3 find the number ​

2 Answers

5 votes

Answer:

2/5--1/4=3

Explanation:

lcm is 20 =8-5=3/20=3 =20

User Morrisda
by
8.1k points
1 vote
Answer is N = 20

Step by step

1/4 of a number means 1/4n
Is removed from is subtract
2/5 of that number means 2/5n
Result is 3 means equal = 3

Put this into an equation

2/5n - 1/4n = 3

Our common denominator is 20

2/5 = 8/20 ( multiplying top and bottom by 4)
1/4 = 5/20 (multiply top and bottom by 5)

8/20n - 5/20n = 3

Subtract

3/20n = 3

Divide both sides by 3/20 to solve for n
When we divide fractions we flip the divisor and multiply

3/20 * 20/3 n = 3 * 20/3

Multiply

n = 20
User Tremoloqui
by
9.2k points

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