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Finding the Fourth Proportional to 870.07, 1,305.05 and 407.95

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Solution

The fourth proportional to 870.07, 1,305.05 and 407.95 is: 611.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.07 : 1,305.05 = 407.95 : x
  2. Step 2: Convert to fraction form
    870.07/1,305.05 = 407.95/x
  3. Step 3: Cross multiply
    870.07x = 1,305.05 × 407.95
  4. Step 4: Simplify right side
    870.07x = 532,396.27
  5. Step 5: Solve for x
    x = 532,396.27/870.07
  6. Step 6: Final answer
    x = 611.90

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.