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Finding the Fourth Proportional to 647.80, 971.40 and 282.40

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Solution

The fourth proportional to 647.80, 971.40 and 282.40 is: 423.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.80 : 971.40 = 282.40 : x
  2. Step 2: Convert to fraction form
    647.80/971.40 = 282.40/x
  3. Step 3: Cross multiply
    647.80x = 971.40 × 282.40
  4. Step 4: Simplify right side
    647.80x = 274,323.36
  5. Step 5: Solve for x
    x = 274,323.36/647.80
  6. Step 6: Final answer
    x = 423.47

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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.