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Finding the Fourth Proportional to 877.90, 1,211.71 and 505.10

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Solution

The fourth proportional to 877.90, 1,211.71 and 505.10 is: 697.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    877.90 : 1,211.71 = 505.10 : x
  2. Step 2: Convert to fraction form
    877.90/1,211.71 = 505.10/x
  3. Step 3: Cross multiply
    877.90x = 1,211.71 × 505.10
  4. Step 4: Simplify right side
    877.90x = 612,032.32
  5. Step 5: Solve for x
    x = 612,032.32/877.90
  6. Step 6: Final answer
    x = 697.15

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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.