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Finding the Fourth Proportional to 630.72, 870.40 and 347.12

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Solution

The fourth proportional to 630.72, 870.40 and 347.12 is: 479.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.72 : 870.40 = 347.12 : x
  2. Step 2: Convert to fraction form
    630.72/870.40 = 347.12/x
  3. Step 3: Cross multiply
    630.72x = 870.40 × 347.12
  4. Step 4: Simplify right side
    630.72x = 302,133.25
  5. Step 5: Solve for x
    x = 302,133.25/630.72
  6. Step 6: Final answer
    x = 479.03

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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.