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Finding the Fourth Proportional to 785.10, 1,177.68 and 420.06

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Solution

The fourth proportional to 785.10, 1,177.68 and 420.06 is: 630.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    785.10 : 1,177.68 = 420.06 : x
  2. Step 2: Convert to fraction form
    785.10/1,177.68 = 420.06/x
  3. Step 3: Cross multiply
    785.10x = 1,177.68 × 420.06
  4. Step 4: Simplify right side
    785.10x = 494,696.26
  5. Step 5: Solve for x
    x = 494,696.26/785.10
  6. Step 6: Final answer
    x = 630.11

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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.