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Finding the Fourth Proportional to 647.79, 972 and 339.90

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Solution

The fourth proportional to 647.79, 972 and 339.90 is: 510.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.79 : 972 = 339.90 : x
  2. Step 2: Convert to fraction form
    647.79/972 = 339.90/x
  3. Step 3: Cross multiply
    647.79x = 972 × 339.90
  4. Step 4: Simplify right side
    647.79x = 330,382.80
  5. Step 5: Solve for x
    x = 330,382.80/647.79
  6. Step 6: Final answer
    x = 510.02

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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.