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Finding the Fourth Proportional to 648.55, 970.80 and 628.30

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Solution

The fourth proportional to 648.55, 970.80 and 628.30 is: 940.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.55 : 970.80 = 628.30 : x
  2. Step 2: Convert to fraction form
    648.55/970.80 = 628.30/x
  3. Step 3: Cross multiply
    648.55x = 970.80 × 628.30
  4. Step 4: Simplify right side
    648.55x = 609,953.64
  5. Step 5: Solve for x
    x = 609,953.64/648.55
  6. Step 6: Final answer
    x = 940.49

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1.5x scale

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.