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Finding the Fourth Proportional to 690.48, 1,035 and 300.70

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Solution

The fourth proportional to 690.48, 1,035 and 300.70 is: 450.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.48 : 1,035 = 300.70 : x
  2. Step 2: Convert to fraction form
    690.48/1,035 = 300.70/x
  3. Step 3: Cross multiply
    690.48x = 1,035 × 300.70
  4. Step 4: Simplify right side
    690.48x = 311,224.50
  5. Step 5: Solve for x
    x = 311,224.50/690.48
  6. Step 6: Final answer
    x = 450.74

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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.