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Finding the Fourth Proportional to 646.90, 970.50 and 214.05

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Solution

The fourth proportional to 646.90, 970.50 and 214.05 is: 321.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.90 : 970.50 = 214.05 : x
  2. Step 2: Convert to fraction form
    646.90/970.50 = 214.05/x
  3. Step 3: Cross multiply
    646.90x = 970.50 × 214.05
  4. Step 4: Simplify right side
    646.90x = 207,739.16
  5. Step 5: Solve for x
    x = 207,739.16/646.90
  6. Step 6: Final answer
    x = 321.13

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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.