Home / 414.04-621.40-208.78

Finding the Fourth Proportional to 414.04, 621.40 and 208.78

Calculator

Solution

The fourth proportional to 414.04, 621.40 and 208.78 is: 313.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    414.04 : 621.40 = 208.78 : x
  2. Step 2: Convert to fraction form
    414.04/621.40 = 208.78/x
  3. Step 3: Cross multiply
    414.04x = 621.40 × 208.78
  4. Step 4: Simplify right side
    414.04x = 129,735.89
  5. Step 5: Solve for x
    x = 129,735.89/414.04
  6. Step 6: Final answer
    x = 313.34

Related Problems

Find fourth proportional to 207.02, 310.70 and 104.39
Half scale
Find fourth proportional to 828.08, 1,242.80 and 417.56
Double scale
Find fourth proportional to 415.04, 622.90 and 209.78
Similar ratio
Find fourth proportional to 621.06, 932.10 and 313.17
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.