Intelligent Math Puzzle – Challenge 81
Enjoy solving math puzzles and critical thinking challenges? If so, then this challenge is just for you. The answer is also given.
Challenge:
What is the last number in the 18th row in the following pattern?
First row: 2
Second row: 3 4
Third row: 5 6 7
Fourth row: 8 9 10 11
…
A- 169
B- 170
C- 171
D- 172
E- 173
The Absolute Best Book to Challenge Your Smart Student!
Original price was: $16.99.$11.99Current price is: $11.99.
Satisfied 123 Students
The correct answer is D.
Each row has one number more than the previous row. The first row has one number, the second row has two numbers, and the 18th row has 18 numbers.
To answer the question, we should find the number of numbers in all 18 rows.
\(1 + 2 + 3 + … + 17 + 18 = \frac{18}{2}(1+18) = 171\)
The first number starts with 2. Therefore, the last number is 172 (171 +1).The Best Books to Ace Algebra
Original price was: $29.99.$14.99Current price is: $14.99.Original price was: $29.99.$14.99Current price is: $14.99.Satisfied 1 StudentsOriginal price was: $24.99.$14.99Current price is: $14.99.Satisfied 92 StudentsOriginal price was: $24.99.$15.99Current price is: $15.99.Satisfied 125 Students
Related to This Article
More math articles
- Algebra Puzzle – Challenge 31
- How to Prepare for the TABE Math Test?
- How to Solve Radical Inequalities?
- How to Find Complex Roots of the Quadratic Equation?
- Top 10 3rd Grade MCAS Math Practice Questions
- How to Find the Area and Circumference of Circles? (+FREE Worksheet!)
- Dollars and Sense: How to Tackle Money Word Problems with Confidence
- Top 10 Tips to Create the TExES Core Subjects Math Study Plan
- High School Placement Test (HSPT): Complete Guide
- HiSET Math Practice Test Questions
What people say about "Intelligent Math Puzzle – Challenge 81 - Effortless Math: We Help Students Learn to LOVE Mathematics"?
No one replied yet.