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Finding the Fourth Proportional to 780.53, 1,170.78 and 493.79

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Solution

The fourth proportional to 780.53, 1,170.78 and 493.79 is: 740.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.53 : 1,170.78 = 493.79 : x
  2. Step 2: Convert to fraction form
    780.53/1,170.78 = 493.79/x
  3. Step 3: Cross multiply
    780.53x = 1,170.78 × 493.79
  4. Step 4: Simplify right side
    780.53x = 578,113.60
  5. Step 5: Solve for x
    x = 578,113.60/780.53
  6. Step 6: Final answer
    x = 740.67

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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.