Home / 723.79-998.82-392.21

Finding the Fourth Proportional to 723.79, 998.82 and 392.21

Calculator

Solution

The fourth proportional to 723.79, 998.82 and 392.21 is: 541.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    723.79 : 998.82 = 392.21 : x
  2. Step 2: Convert to fraction form
    723.79/998.82 = 392.21/x
  3. Step 3: Cross multiply
    723.79x = 998.82 × 392.21
  4. Step 4: Simplify right side
    723.79x = 391,745.23
  5. Step 5: Solve for x
    x = 391,745.23/723.79
  6. Step 6: Final answer
    x = 541.25

Related Problems

Find fourth proportional to 361.89, 499.41 and 196.11
Half scale
Find fourth proportional to 1,447.57, 1,997.63 and 784.42
Double scale
Find fourth proportional to 724.79, 1,000.19 and 393.21
Similar ratio
Find fourth proportional to 1,085.68, 1,498.22 and 588.32
1.5x scale

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.