Home / 280.75-428.75

Finding the Third Proportional to 280.75 and 428.75

Calculator

Solution

The third proportional to 280.75 and 428.75 is: 654.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.75 : 428.75 = 428.75 : x
  2. Step 2: Convert to fraction form
    280.75/428.75 = 428.75/x
  3. Step 3: Cross multiply
    280.75x = 428.75 × 428.75
  4. Step 4: Simplify right side
    280.75x = 183,826.56
  5. Step 5: Solve for x
    x = 183,826.56/280.75
  6. Step 6: Final answer
    x = 654.77

Related Problems

Find third proportional to 140.38 and 214.38
Half scale
Find third proportional to 561.50 and 857.50
Double scale
Find third proportional to 283 and 432
Similar ratio
Find third proportional to 421.13 and 643.13
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.53) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.