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Finding the Fourth Proportional to 770.09, 1,155.29 and 380.07

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Solution

The fourth proportional to 770.09, 1,155.29 and 380.07 is: 570.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.09 : 1,155.29 = 380.07 : x
  2. Step 2: Convert to fraction form
    770.09/1,155.29 = 380.07/x
  3. Step 3: Cross multiply
    770.09x = 1,155.29 × 380.07
  4. Step 4: Simplify right side
    770.09x = 439,089.17
  5. Step 5: Solve for x
    x = 439,089.17/770.09
  6. Step 6: Final answer
    x = 570.18

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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.