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Finding the Fourth Proportional to 646.60, 891.86 and 384.40

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Solution

The fourth proportional to 646.60, 891.86 and 384.40 is: 530.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.60 : 891.86 = 384.40 : x
  2. Step 2: Convert to fraction form
    646.60/891.86 = 384.40/x
  3. Step 3: Cross multiply
    646.60x = 891.86 × 384.40
  4. Step 4: Simplify right side
    646.60x = 342,830.98
  5. Step 5: Solve for x
    x = 342,830.98/646.60
  6. Step 6: Final answer
    x = 530.21

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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.