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Finding the Fourth Proportional to 870.36, 1,304.93 and 407.89

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Solution

The fourth proportional to 870.36, 1,304.93 and 407.89 is: 611.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.36 : 1,304.93 = 407.89 : x
  2. Step 2: Convert to fraction form
    870.36/1,304.93 = 407.89/x
  3. Step 3: Cross multiply
    870.36x = 1,304.93 × 407.89
  4. Step 4: Simplify right side
    870.36x = 532,267.90
  5. Step 5: Solve for x
    x = 532,267.90/870.36
  6. Step 6: Final answer
    x = 611.55

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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.