Home / 463.78-639.95-256.78

Finding the Fourth Proportional to 463.78, 639.95 and 256.78

Calculator

Solution

The fourth proportional to 463.78, 639.95 and 256.78 is: 354.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    463.78 : 639.95 = 256.78 : x
  2. Step 2: Convert to fraction form
    463.78/639.95 = 256.78/x
  3. Step 3: Cross multiply
    463.78x = 639.95 × 256.78
  4. Step 4: Simplify right side
    463.78x = 164,326.36
  5. Step 5: Solve for x
    x = 164,326.36/463.78
  6. Step 6: Final answer
    x = 354.32

Related Problems

Find fourth proportional to 231.89, 319.98 and 128.39
Half scale
Find fourth proportional to 927.56, 1,279.90 and 513.56
Double scale
Find fourth proportional to 464.78, 641.33 and 257.78
Similar ratio
Find fourth proportional to 695.67, 959.93 and 385.17
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.