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Finding the Fourth Proportional to 1,235.80, 1,854.90 and 620.20

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Solution

The fourth proportional to 1,235.80, 1,854.90 and 620.20 is: 930.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,235.80 : 1,854.90 = 620.20 : x
  2. Step 2: Convert to fraction form
    1,235.80/1,854.90 = 620.20/x
  3. Step 3: Cross multiply
    1,235.80x = 1,854.90 × 620.20
  4. Step 4: Simplify right side
    1,235.80x = 1,150,408.98
  5. Step 5: Solve for x
    x = 1,150,408.98/1,235.80
  6. Step 6: Final answer
    x = 930.90

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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.