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Finding the Fourth Proportional to 770.20, 1,155.36 and 380.41

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Solution

The fourth proportional to 770.20, 1,155.36 and 380.41 is: 570.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.20 : 1,155.36 = 380.41 : x
  2. Step 2: Convert to fraction form
    770.20/1,155.36 = 380.41/x
  3. Step 3: Cross multiply
    770.20x = 1,155.36 × 380.41
  4. Step 4: Simplify right side
    770.20x = 439,510.50
  5. Step 5: Solve for x
    x = 439,510.50/770.20
  6. Step 6: Final answer
    x = 570.64

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Double scale
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1.5x scale

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.