Home / 580.64-870.40-387.84

Finding the Fourth Proportional to 580.64, 870.40 and 387.84

Calculator

Solution

The fourth proportional to 580.64, 870.40 and 387.84 is: 581.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    580.64 : 870.40 = 387.84 : x
  2. Step 2: Convert to fraction form
    580.64/870.40 = 387.84/x
  3. Step 3: Cross multiply
    580.64x = 870.40 × 387.84
  4. Step 4: Simplify right side
    580.64x = 337,575.94
  5. Step 5: Solve for x
    x = 337,575.94/580.64
  6. Step 6: Final answer
    x = 581.39

Related Problems

Find fourth proportional to 290.32, 435.20 and 193.92
Half scale
Find fourth proportional to 1,161.28, 1,740.80 and 775.68
Double scale
Find fourth proportional to 581.64, 871.90 and 388.84
Similar ratio
Find fourth proportional to 870.96, 1,305.60 and 581.76
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.