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Finding the Fourth Proportional to 780.99, 1,077.53 and 486.15

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Solution

The fourth proportional to 780.99, 1,077.53 and 486.15 is: 670.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.99 : 1,077.53 = 486.15 : x
  2. Step 2: Convert to fraction form
    780.99/1,077.53 = 486.15/x
  3. Step 3: Cross multiply
    780.99x = 1,077.53 × 486.15
  4. Step 4: Simplify right side
    780.99x = 523,841.21
  5. Step 5: Solve for x
    x = 523,841.21/780.99
  6. Step 6: Final answer
    x = 670.74

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.