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Finding the Fourth Proportional to 646.40, 891.68 and 439.04

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Solution

The fourth proportional to 646.40, 891.68 and 439.04 is: 605.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.40 : 891.68 = 439.04 : x
  2. Step 2: Convert to fraction form
    646.40/891.68 = 439.04/x
  3. Step 3: Cross multiply
    646.40x = 891.68 × 439.04
  4. Step 4: Simplify right side
    646.40x = 391,483.19
  5. Step 5: Solve for x
    x = 391,483.19/646.40
  6. Step 6: Final answer
    x = 605.64

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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.