Home / 69-149

Finding the Third Proportional to 69 and 149

Calculator

Solution

The third proportional to 69 and 149 is: 321.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    69 : 149 = 149 : x
  2. Step 2: Convert to fraction form
    69/149 = 149/x
  3. Step 3: Cross multiply
    69x = 149 × 149
  4. Step 4: Simplify right side
    69x = 22,201
  5. Step 5: Solve for x
    x = 22,201/69
  6. Step 6: Final answer
    x = 321.75

Related Problems

Find third proportional to 34.50 and 74.50
Half scale
Find third proportional to 138 and 298
Double scale
Find third proportional to 71 and 153
Similar ratio
Find third proportional to 103.50 and 223.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.16) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.