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Finding the Fourth Proportional to 677.40, 1,013.70 and 619.80

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Solution

The fourth proportional to 677.40, 1,013.70 and 619.80 is: 927.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    677.40 : 1,013.70 = 619.80 : x
  2. Step 2: Convert to fraction form
    677.40/1,013.70 = 619.80/x
  3. Step 3: Cross multiply
    677.40x = 1,013.70 × 619.80
  4. Step 4: Simplify right side
    677.40x = 628,291.26
  5. Step 5: Solve for x
    x = 628,291.26/677.40
  6. Step 6: Final answer
    x = 927.50

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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.