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Finding the Fourth Proportional to 1,981.59, 2,972.35 and 520.75

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Solution

The fourth proportional to 1,981.59, 2,972.35 and 520.75 is: 781.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,981.59 : 2,972.35 = 520.75 : x
  2. Step 2: Convert to fraction form
    1,981.59/2,972.35 = 520.75/x
  3. Step 3: Cross multiply
    1,981.59x = 2,972.35 × 520.75
  4. Step 4: Simplify right side
    1,981.59x = 1,547,851.26
  5. Step 5: Solve for x
    x = 1,547,851.26/1,981.59
  6. Step 6: Final answer
    x = 781.12

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1.5x scale

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.