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Finding the Fourth Proportional to 430.45, 646.54 and 257.46

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Solution

The fourth proportional to 430.45, 646.54 and 257.46 is: 386.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.45 : 646.54 = 257.46 : x
  2. Step 2: Convert to fraction form
    430.45/646.54 = 257.46/x
  3. Step 3: Cross multiply
    430.45x = 646.54 × 257.46
  4. Step 4: Simplify right side
    430.45x = 166,458.19
  5. Step 5: Solve for x
    x = 166,458.19/430.45
  6. Step 6: Final answer
    x = 386.71

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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.