Home / 287-408.75

Finding the Third Proportional to 287 and 408.75

Calculator

Solution

The third proportional to 287 and 408.75 is: 582.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    287 : 408.75 = 408.75 : x
  2. Step 2: Convert to fraction form
    287/408.75 = 408.75/x
  3. Step 3: Cross multiply
    287x = 408.75 × 408.75
  4. Step 4: Simplify right side
    287x = 167,076.56
  5. Step 5: Solve for x
    x = 167,076.56/287
  6. Step 6: Final answer
    x = 582.15

Related Problems

Find third proportional to 143.50 and 204.38
Half scale
Find third proportional to 574 and 817.50
Double scale
Find third proportional to 289 and 412
Similar ratio
Find third proportional to 430.50 and 613.13
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.42) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.