Home / 392.75-638.75

Finding the Third Proportional to 392.75 and 638.75

Calculator

Solution

The third proportional to 392.75 and 638.75 is: 1,038.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    392.75 : 638.75 = 638.75 : x
  2. Step 2: Convert to fraction form
    392.75/638.75 = 638.75/x
  3. Step 3: Cross multiply
    392.75x = 638.75 × 638.75
  4. Step 4: Simplify right side
    392.75x = 408,001.56
  5. Step 5: Solve for x
    x = 408,001.56/392.75
  6. Step 6: Final answer
    x = 1,038.83

Related Problems

Find third proportional to 196.38 and 319.38
Half scale
Find third proportional to 785.50 and 1,277.50
Double scale
Find third proportional to 395 and 642
Similar ratio
Find third proportional to 589.13 and 958.13
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.63) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.