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Finding the Fourth Proportional to 653.80, 980.70 and 621.80

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Solution

The fourth proportional to 653.80, 980.70 and 621.80 is: 932.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.80 : 980.70 = 621.80 : x
  2. Step 2: Convert to fraction form
    653.80/980.70 = 621.80/x
  3. Step 3: Cross multiply
    653.80x = 980.70 × 621.80
  4. Step 4: Simplify right side
    653.80x = 609,799.26
  5. Step 5: Solve for x
    x = 609,799.26/653.80
  6. Step 6: Final answer
    x = 932.70

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Double scale
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Similar ratio
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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.