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Finding the Fourth Proportional to 870.99, 1,306.35 and 285.99

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Solution

The fourth proportional to 870.99, 1,306.35 and 285.99 is: 428.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.99 : 1,306.35 = 285.99 : x
  2. Step 2: Convert to fraction form
    870.99/1,306.35 = 285.99/x
  3. Step 3: Cross multiply
    870.99x = 1,306.35 × 285.99
  4. Step 4: Simplify right side
    870.99x = 373,595.07
  5. Step 5: Solve for x
    x = 373,595.07/870.99
  6. Step 6: Final answer
    x = 428.93

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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.