Home / 256.78-553.78

Finding the Third Proportional to 256.78 and 553.78

Calculator

Solution

The third proportional to 256.78 and 553.78 is: 1,194.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.78 : 553.78 = 553.78 : x
  2. Step 2: Convert to fraction form
    256.78/553.78 = 553.78/x
  3. Step 3: Cross multiply
    256.78x = 553.78 × 553.78
  4. Step 4: Simplify right side
    256.78x = 306,673.67
  5. Step 5: Solve for x
    x = 306,673.67/256.78
  6. Step 6: Final answer
    x = 1,194.30

Related Problems

Find third proportional to 128.39 and 276.89
Half scale
Find third proportional to 513.56 and 1,107.56
Double scale
Find third proportional to 259 and 558
Similar ratio
Find third proportional to 385.17 and 830.67
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (2.16) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.