Home / 359.92-539.74-128.78

Finding the Fourth Proportional to 359.92, 539.74 and 128.78

Calculator

Solution

The fourth proportional to 359.92, 539.74 and 128.78 is: 193.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    359.92 : 539.74 = 128.78 : x
  2. Step 2: Convert to fraction form
    359.92/539.74 = 128.78/x
  3. Step 3: Cross multiply
    359.92x = 539.74 × 128.78
  4. Step 4: Simplify right side
    359.92x = 69,507.72
  5. Step 5: Solve for x
    x = 69,507.72/359.92
  6. Step 6: Final answer
    x = 193.12

Related Problems

Find fourth proportional to 179.96, 269.87 and 64.39
Half scale
Find fourth proportional to 719.84, 1,079.48 and 257.56
Double scale
Find fourth proportional to 360.92, 541.24 and 129.78
Similar ratio
Find fourth proportional to 539.88, 809.61 and 193.17
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.