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Finding the Fourth Proportional to 780.16, 1,170.10 and 260.17

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Solution

The fourth proportional to 780.16, 1,170.10 and 260.17 is: 390.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.16 : 1,170.10 = 260.17 : x
  2. Step 2: Convert to fraction form
    780.16/1,170.10 = 260.17/x
  3. Step 3: Cross multiply
    780.16x = 1,170.10 × 260.17
  4. Step 4: Simplify right side
    780.16x = 304,424.92
  5. Step 5: Solve for x
    x = 304,424.92/780.16
  6. Step 6: Final answer
    x = 390.21

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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.