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Finding the Fourth Proportional to 770.06, 1,062.69 and 420.75

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Solution

The fourth proportional to 770.06, 1,062.69 and 420.75 is: 580.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    770.06 : 1,062.69 = 420.75 : x
  2. Step 2: Convert to fraction form
    770.06/1,062.69 = 420.75/x
  3. Step 3: Cross multiply
    770.06x = 1,062.69 × 420.75
  4. Step 4: Simplify right side
    770.06x = 447,125.24
  5. Step 5: Solve for x
    x = 447,125.24/770.06
  6. Step 6: Final answer
    x = 580.64

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.