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Finding the Fourth Proportional to 657.81, 907.80 and 378.10

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Solution

The fourth proportional to 657.81, 907.80 and 378.10 is: 521.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.81 : 907.80 = 378.10 : x
  2. Step 2: Convert to fraction form
    657.81/907.80 = 378.10/x
  3. Step 3: Cross multiply
    657.81x = 907.80 × 378.10
  4. Step 4: Simplify right side
    657.81x = 343,235.02
  5. Step 5: Solve for x
    x = 343,235.02/657.81
  6. Step 6: Final answer
    x = 521.79

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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.