Home / 1,387.80-2,081.52-522

Finding the Fourth Proportional to 1,387.80, 2,081.52 and 522

Calculator

Solution

The fourth proportional to 1,387.80, 2,081.52 and 522 is: 782.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,387.80 : 2,081.52 = 522 : x
  2. Step 2: Convert to fraction form
    1,387.80/2,081.52 = 522/x
  3. Step 3: Cross multiply
    1,387.80x = 2,081.52 × 522
  4. Step 4: Simplify right side
    1,387.80x = 1,086,553.44
  5. Step 5: Solve for x
    x = 1,086,553.44/1,387.80
  6. Step 6: Final answer
    x = 782.93

Related Problems

Find fourth proportional to 693.90, 1,040.76 and 261
Half scale
Find fourth proportional to 2,775.60, 4,163.04 and 1,044
Double scale
Find fourth proportional to 1,388.80, 2,083.02 and 523
Similar ratio
Find fourth proportional to 2,081.70, 3,122.28 and 783
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.