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Finding the Fourth Proportional to 654.21, 980.78 and 410.40

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Solution

The fourth proportional to 654.21, 980.78 and 410.40 is: 615.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.21 : 980.78 = 410.40 : x
  2. Step 2: Convert to fraction form
    654.21/980.78 = 410.40/x
  3. Step 3: Cross multiply
    654.21x = 980.78 × 410.40
  4. Step 4: Simplify right side
    654.21x = 402,510.06
  5. Step 5: Solve for x
    x = 402,510.06/654.21
  6. Step 6: Final answer
    x = 615.26

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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.