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Finding the Fourth Proportional to 646.40, 969.96 and 387.02

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Solution

The fourth proportional to 646.40, 969.96 and 387.02 is: 580.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.40 : 969.96 = 387.02 : x
  2. Step 2: Convert to fraction form
    646.40/969.96 = 387.02/x
  3. Step 3: Cross multiply
    646.40x = 969.96 × 387.02
  4. Step 4: Simplify right side
    646.40x = 375,389.07
  5. Step 5: Solve for x
    x = 375,389.07/646.40
  6. Step 6: Final answer
    x = 580.74

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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.