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Finding the Fourth Proportional to 628.48, 870.98 and 619.67

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Solution

The fourth proportional to 628.48, 870.98 and 619.67 is: 858.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.48 : 870.98 = 619.67 : x
  2. Step 2: Convert to fraction form
    628.48/870.98 = 619.67/x
  3. Step 3: Cross multiply
    628.48x = 870.98 × 619.67
  4. Step 4: Simplify right side
    628.48x = 539,719.26
  5. Step 5: Solve for x
    x = 539,719.26/628.48
  6. Step 6: Final answer
    x = 858.77

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.