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Finding the Fourth Proportional to 816.95, 1,127.33 and 485.40

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Solution

The fourth proportional to 816.95, 1,127.33 and 485.40 is: 669.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    816.95 : 1,127.33 = 485.40 : x
  2. Step 2: Convert to fraction form
    816.95/1,127.33 = 485.40/x
  3. Step 3: Cross multiply
    816.95x = 1,127.33 × 485.40
  4. Step 4: Simplify right side
    816.95x = 547,205.98
  5. Step 5: Solve for x
    x = 547,205.98/816.95
  6. Step 6: Final answer
    x = 669.82

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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.