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Finding the Fourth Proportional to 858.06, 1,287.11 and 310.30

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Solution

The fourth proportional to 858.06, 1,287.11 and 310.30 is: 465.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.06 : 1,287.11 = 310.30 : x
  2. Step 2: Convert to fraction form
    858.06/1,287.11 = 310.30/x
  3. Step 3: Cross multiply
    858.06x = 1,287.11 × 310.30
  4. Step 4: Simplify right side
    858.06x = 399,390.23
  5. Step 5: Solve for x
    x = 399,390.23/858.06
  6. Step 6: Final answer
    x = 465.46

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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.