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Finding the Fourth Proportional to 1,210.10, 1,813.80 and 690.35

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Solution

The fourth proportional to 1,210.10, 1,813.80 and 690.35 is: 1,034.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,210.10 : 1,813.80 = 690.35 : x
  2. Step 2: Convert to fraction form
    1,210.10/1,813.80 = 690.35/x
  3. Step 3: Cross multiply
    1,210.10x = 1,813.80 × 690.35
  4. Step 4: Simplify right side
    1,210.10x = 1,252,156.83
  5. Step 5: Solve for x
    x = 1,252,156.83/1,210.10
  6. Step 6: Final answer
    x = 1,034.75

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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.