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Finding the Fourth Proportional to 419.80, 628.56 and 316.84

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Solution

The fourth proportional to 419.80, 628.56 and 316.84 is: 474.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.80 : 628.56 = 316.84 : x
  2. Step 2: Convert to fraction form
    419.80/628.56 = 316.84/x
  3. Step 3: Cross multiply
    419.80x = 628.56 × 316.84
  4. Step 4: Simplify right side
    419.80x = 199,152.95
  5. Step 5: Solve for x
    x = 199,152.95/419.80
  6. Step 6: Final answer
    x = 474.40

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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.