Home / 780.25-1,170.05-317.72

Finding the Fourth Proportional to 780.25, 1,170.05 and 317.72

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Solution

The fourth proportional to 780.25, 1,170.05 and 317.72 is: 476.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.25 : 1,170.05 = 317.72 : x
  2. Step 2: Convert to fraction form
    780.25/1,170.05 = 317.72/x
  3. Step 3: Cross multiply
    780.25x = 1,170.05 × 317.72
  4. Step 4: Simplify right side
    780.25x = 371,742.83
  5. Step 5: Solve for x
    x = 371,742.83/780.25
  6. Step 6: Final answer
    x = 476.44

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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.