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Finding the Fourth Proportional to 770.19, 1,062.89 and 420.89

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Solution

The fourth proportional to 770.19, 1,062.89 and 420.89 is: 580.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.19 : 1,062.89 = 420.89 : x
  2. Step 2: Convert to fraction form
    770.19/1,062.89 = 420.89/x
  3. Step 3: Cross multiply
    770.19x = 1,062.89 × 420.89
  4. Step 4: Simplify right side
    770.19x = 447,359.77
  5. Step 5: Solve for x
    x = 447,359.77/770.19
  6. Step 6: Final answer
    x = 580.84

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1.5x scale

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.