Home / 81,658-128,321

Finding the Third Proportional to 81,658 and 128,321

Calculator

Solution

The third proportional to 81,658 and 128,321 is: 201,649.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    81,658 : 128,321 = 128,321 : x
  2. Step 2: Convert to fraction form
    81,658/128,321 = 128,321/x
  3. Step 3: Cross multiply
    81,658x = 128,321 × 128,321
  4. Step 4: Simplify right side
    81,658x = 16,466,279,041
  5. Step 5: Solve for x
    x = 16,466,279,041/81,658
  6. Step 6: Final answer
    x = 201,649.31

Related Problems

Find third proportional to 40,829 and 64,160.50
Half scale
Find third proportional to 163,316 and 256,642
Double scale
Find third proportional to 81,660 and 128,324
Similar ratio
Find third proportional to 122,487 and 192,481.50
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.57) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.