Home / 879.80-1,319.55-386.42

Finding the Fourth Proportional to 879.80, 1,319.55 and 386.42

Calculator

Solution

The fourth proportional to 879.80, 1,319.55 and 386.42 is: 579.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    879.80 : 1,319.55 = 386.42 : x
  2. Step 2: Convert to fraction form
    879.80/1,319.55 = 386.42/x
  3. Step 3: Cross multiply
    879.80x = 1,319.55 × 386.42
  4. Step 4: Simplify right side
    879.80x = 509,900.51
  5. Step 5: Solve for x
    x = 509,900.51/879.80
  6. Step 6: Final answer
    x = 579.56

Related Problems

Find fourth proportional to 439.90, 659.78 and 193.21
Half scale
Find fourth proportional to 1,759.60, 2,639.10 and 772.84
Double scale
Find fourth proportional to 880.80, 1,321.05 and 387.42
Similar ratio
Find fourth proportional to 1,319.70, 1,979.33 and 579.63
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.