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Finding the Fourth Proportional to 430.58, 646.08 and 199.40

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Solution

The fourth proportional to 430.58, 646.08 and 199.40 is: 299.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.58 : 646.08 = 199.40 : x
  2. Step 2: Convert to fraction form
    430.58/646.08 = 199.40/x
  3. Step 3: Cross multiply
    430.58x = 646.08 × 199.40
  4. Step 4: Simplify right side
    430.58x = 128,828.35
  5. Step 5: Solve for x
    x = 128,828.35/430.58
  6. Step 6: Final answer
    x = 299.20

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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.