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Finding the Fourth Proportional to 677.90, 935.42 and 398.14

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Solution

The fourth proportional to 677.90, 935.42 and 398.14 is: 549.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    677.90 : 935.42 = 398.14 : x
  2. Step 2: Convert to fraction form
    677.90/935.42 = 398.14/x
  3. Step 3: Cross multiply
    677.90x = 935.42 × 398.14
  4. Step 4: Simplify right side
    677.90x = 372,428.12
  5. Step 5: Solve for x
    x = 372,428.12/677.90
  6. Step 6: Final answer
    x = 549.39

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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.