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Finding the Fourth Proportional to 630.54, 870.45 and 421.07

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Solution

The fourth proportional to 630.54, 870.45 and 421.07 is: 581.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.54 : 870.45 = 421.07 : x
  2. Step 2: Convert to fraction form
    630.54/870.45 = 421.07/x
  3. Step 3: Cross multiply
    630.54x = 870.45 × 421.07
  4. Step 4: Simplify right side
    630.54x = 366,520.38
  5. Step 5: Solve for x
    x = 366,520.38/630.54
  6. Step 6: Final answer
    x = 581.28

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1.5x scale

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.