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**The mean of ten positive numbers is 16. When another number is added, the mean becomes 18. Find the eleventh number**.

**A.**** 3**

**B.**** 16**

**C.**** 38**

**D.**** 30**

**QUICK ANSWER…**

**C**

**DETAILS…**

**If t****he mean of ten positive numbers is 16****, and when ****another number is added**** to bring ****the mean ****to**** 18****,**** the eleventh number**** will be =**

**Mean = sum of all numbers/ how many numbers being added**

**Let sum of all the numbers = A**

**Mean = A/10**

**A = 10 × mean**

**A = 10 × 16**

**A = 160**

**If another number is added, let the number be = B**

**New mean = (A + B)/11**

**18 = (160 + B)/11**

**18 × 11 = 160 + B**

**198 = 160 + B**

**B = 198 – 160**

**B = 38**

**Now for the right answer to the above question:**

**Option A is incorrect.****Option B is not correct.****C is correct.****D is not the correct answer.**

**KEY-POINTS…**

**You may please note these/this:**

**Mean = sum of numbers / number of occurrence of numbers**

**If you love our answers, you can simply join our community and also provide answers like this, fellow learners like you will appreciate it.**

**/ culled from 20****21**** JAMB-UTME**** MATHEMATICS**** question**** 23 ****/**