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Finding the Fourth Proportional to 621.63, 856.38 and 434.79

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Solution

The fourth proportional to 621.63, 856.38 and 434.79 is: 598.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.63 : 856.38 = 434.79 : x
  2. Step 2: Convert to fraction form
    621.63/856.38 = 434.79/x
  3. Step 3: Cross multiply
    621.63x = 856.38 × 434.79
  4. Step 4: Simplify right side
    621.63x = 372,343.29
  5. Step 5: Solve for x
    x = 372,343.29/621.63
  6. Step 6: Final answer
    x = 598.98

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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.