Home / 634.78-875.84-398.77

Finding the Fourth Proportional to 634.78, 875.84 and 398.77

Calculator

Solution

The fourth proportional to 634.78, 875.84 and 398.77 is: 550.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    634.78 : 875.84 = 398.77 : x
  2. Step 2: Convert to fraction form
    634.78/875.84 = 398.77/x
  3. Step 3: Cross multiply
    634.78x = 875.84 × 398.77
  4. Step 4: Simplify right side
    634.78x = 349,254.53
  5. Step 5: Solve for x
    x = 349,254.53/634.78
  6. Step 6: Final answer
    x = 550.20

Related Problems

Find fourth proportional to 317.39, 437.92 and 199.38
Half scale
Find fourth proportional to 1,269.56, 1,751.67 and 797.54
Double scale
Find fourth proportional to 635.78, 877.21 and 399.77
Similar ratio
Find fourth proportional to 952.17, 1,313.75 and 598.15
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.