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Finding the Fourth Proportional to 615.06, 921.30 and 419.40

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Solution

The fourth proportional to 615.06, 921.30 and 419.40 is: 628.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.06 : 921.30 = 419.40 : x
  2. Step 2: Convert to fraction form
    615.06/921.30 = 419.40/x
  3. Step 3: Cross multiply
    615.06x = 921.30 × 419.40
  4. Step 4: Simplify right side
    615.06x = 386,393.22
  5. Step 5: Solve for x
    x = 386,393.22/615.06
  6. Step 6: Final answer
    x = 628.22

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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.