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Finding the Fourth Proportional to 785.19, 1,090.32 and 778.71

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Solution

The fourth proportional to 785.19, 1,090.32 and 778.71 is: 1,081.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    785.19 : 1,090.32 = 778.71 : x
  2. Step 2: Convert to fraction form
    785.19/1,090.32 = 778.71/x
  3. Step 3: Cross multiply
    785.19x = 1,090.32 × 778.71
  4. Step 4: Simplify right side
    785.19x = 849,043.09
  5. Step 5: Solve for x
    x = 849,043.09/785.19
  6. Step 6: Final answer
    x = 1,081.32

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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.