Home / 1,128.70-1,557.56-631.30

Finding the Fourth Proportional to 1,128.70, 1,557.56 and 631.30

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Solution

The fourth proportional to 1,128.70, 1,557.56 and 631.30 is: 871.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,128.70 : 1,557.56 = 631.30 : x
  2. Step 2: Convert to fraction form
    1,128.70/1,557.56 = 631.30/x
  3. Step 3: Cross multiply
    1,128.70x = 1,557.56 × 631.30
  4. Step 4: Simplify right side
    1,128.70x = 983,287.63
  5. Step 5: Solve for x
    x = 983,287.63/1,128.70
  6. Step 6: Final answer
    x = 871.17

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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.