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Finding the Fourth Proportional to 858.34, 1,287.51 and 310.39

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Solution

The fourth proportional to 858.34, 1,287.51 and 310.39 is: 465.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    858.34 : 1,287.51 = 310.39 : x
  2. Step 2: Convert to fraction form
    858.34/1,287.51 = 310.39/x
  3. Step 3: Cross multiply
    858.34x = 1,287.51 × 310.39
  4. Step 4: Simplify right side
    858.34x = 399,636.32
  5. Step 5: Solve for x
    x = 399,636.32/858.34
  6. Step 6: Final answer
    x = 465.59

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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.