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Finding the Fourth Proportional to 770.23, 1,155.61 and 380.51

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Solution

The fourth proportional to 770.23, 1,155.61 and 380.51 is: 570.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.23 : 1,155.61 = 380.51 : x
  2. Step 2: Convert to fraction form
    770.23/1,155.61 = 380.51/x
  3. Step 3: Cross multiply
    770.23x = 1,155.61 × 380.51
  4. Step 4: Simplify right side
    770.23x = 439,720.19
  5. Step 5: Solve for x
    x = 439,720.19/770.23
  6. Step 6: Final answer
    x = 570.89

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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.