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Finding the Fourth Proportional to 710.21, 980.30 and 489.71

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Solution

The fourth proportional to 710.21, 980.30 and 489.71 is: 675.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    710.21 : 980.30 = 489.71 : x
  2. Step 2: Convert to fraction form
    710.21/980.30 = 489.71/x
  3. Step 3: Cross multiply
    710.21x = 980.30 × 489.71
  4. Step 4: Simplify right side
    710.21x = 480,062.71
  5. Step 5: Solve for x
    x = 480,062.71/710.21
  6. Step 6: Final answer
    x = 675.94

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.