You need to know the least common denominator (LCD) of 81 and 5 if you want to add or subtract two fractions with 81 and 5 as denominators.
The least common denominator, also called lowest common denominator (LCD), of 81 and 5 is 405.
Here is a math problem example where you need to know the LCD of 81 and 5 to solve:
3/81 + 2/5 = ?
Step 1) Take the LCD and divide each denominator by it as follows:
405/81 = 5
405/5 = 81
Step 2) Multiply each nominator with the respective answers from Step 1:
3 x 5 = 15
2 x 81 = 162
Step 3) Put it all together to solve the problem:
15/405 + 162/405 = 177/405
= 3/81 + 2/5 = 177/405
It's that easy! Once again, the lowest common denominator (LCD) of 81 and 5 is as follows:
405
Find Least Common Denominators
Enter another two numbers below to find the Least Common Denominator.