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Finding the Fourth Proportional to 1,288.80, 1,779.14 and 1,242.63

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Solution

The fourth proportional to 1,288.80, 1,779.14 and 1,242.63 is: 1,715.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,288.80 : 1,779.14 = 1,242.63 : x
  2. Step 2: Convert to fraction form
    1,288.80/1,779.14 = 1,242.63/x
  3. Step 3: Cross multiply
    1,288.80x = 1,779.14 × 1,242.63
  4. Step 4: Simplify right side
    1,288.80x = 2,210,812.74
  5. Step 5: Solve for x
    x = 2,210,812.74/1,288.80
  6. Step 6: Final answer
    x = 1,715.40

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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.