Home / 428.79-640.20-382.62

Finding the Fourth Proportional to 428.79, 640.20 and 382.62

Calculator

Solution

The fourth proportional to 428.79, 640.20 and 382.62 is: 571.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.79 : 640.20 = 382.62 : x
  2. Step 2: Convert to fraction form
    428.79/640.20 = 382.62/x
  3. Step 3: Cross multiply
    428.79x = 640.20 × 382.62
  4. Step 4: Simplify right side
    428.79x = 244,953.32
  5. Step 5: Solve for x
    x = 244,953.32/428.79
  6. Step 6: Final answer
    x = 571.27

Related Problems

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.