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Finding the Fourth Proportional to 657.80, 907.92 and 378.20

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Solution

The fourth proportional to 657.80, 907.92 and 378.20 is: 522.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.80 : 907.92 = 378.20 : x
  2. Step 2: Convert to fraction form
    657.80/907.92 = 378.20/x
  3. Step 3: Cross multiply
    657.80x = 907.92 × 378.20
  4. Step 4: Simplify right side
    657.80x = 343,372.51
  5. Step 5: Solve for x
    x = 343,372.51/657.80
  6. Step 6: Final answer
    x = 522.00

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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.