Given Log3=0.4772, log7=0.8451, log5=0.6990, log2=0.3010, how do you evaluate Log21? Precalculus Properties of Logarithmic Functions Common Logs 1 Answer Harish Chandra Rajpoot Jul 11, 2018 #1.3223# Explanation: #\Log(21)# #=\log(3\times 7)# #=\log3+\log7# #=0.4772+0.8451# #=1.3223# Answer link Related questions What is the common logarithm of 10? How do I find the common logarithm of a number? What is a common logarithm or common log? What are common mistakes students make with common log? How do I find the common logarithm of 589,000? How do I find the number whose common logarithm is 2.6025? What is the common logarithm of 54.29? What is the value of the common logarithm log 10,000? What is #log_10 10#? How do I work in #log_10# in Excel? See all questions in Common Logs Impact of this question 3433 views around the world You can reuse this answer Creative Commons License