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Finding the Fourth Proportional to 646.12, 891.65 and 380.57

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Solution

The fourth proportional to 646.12, 891.65 and 380.57 is: 525.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.12 : 891.65 = 380.57 : x
  2. Step 2: Convert to fraction form
    646.12/891.65 = 380.57/x
  3. Step 3: Cross multiply
    646.12x = 891.65 × 380.57
  4. Step 4: Simplify right side
    646.12x = 339,336.99
  5. Step 5: Solve for x
    x = 339,336.99/646.12
  6. Step 6: Final answer
    x = 525.19

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.