Home / 310.78-455.91

Finding the Third Proportional to 310.78 and 455.91

Calculator

Solution

The third proportional to 310.78 and 455.91 is: 668.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.78 : 455.91 = 455.91 : x
  2. Step 2: Convert to fraction form
    310.78/455.91 = 455.91/x
  3. Step 3: Cross multiply
    310.78x = 455.91 × 455.91
  4. Step 4: Simplify right side
    310.78x = 207,850.51
  5. Step 5: Solve for x
    x = 207,850.51/310.78
  6. Step 6: Final answer
    x = 668.80

Related Problems

Find third proportional to 155.39 and 227.95
Half scale
Find third proportional to 621.56 and 911.81
Double scale
Find third proportional to 313 and 459
Similar ratio
Find third proportional to 466.17 and 683.86
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.47) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.