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Finding the Fourth Proportional to 630.77, 870.89 and 394.81

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Solution

The fourth proportional to 630.77, 870.89 and 394.81 is: 545.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.77 : 870.89 = 394.81 : x
  2. Step 2: Convert to fraction form
    630.77/870.89 = 394.81/x
  3. Step 3: Cross multiply
    630.77x = 870.89 × 394.81
  4. Step 4: Simplify right side
    630.77x = 343,837.27
  5. Step 5: Solve for x
    x = 343,837.27/630.77
  6. Step 6: Final answer
    x = 545.11

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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.