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Finding the Fourth Proportional to 1,311.85, 1,810.47 and 722.50

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Solution

The fourth proportional to 1,311.85, 1,810.47 and 722.50 is: 997.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,311.85 : 1,810.47 = 722.50 : x
  2. Step 2: Convert to fraction form
    1,311.85/1,810.47 = 722.50/x
  3. Step 3: Cross multiply
    1,311.85x = 1,810.47 × 722.50
  4. Step 4: Simplify right side
    1,311.85x = 1,308,064.58
  5. Step 5: Solve for x
    x = 1,308,064.58/1,311.85
  6. Step 6: Final answer
    x = 997.11

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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.