Home / 338.86-507.38-278.72

Finding the Fourth Proportional to 338.86, 507.38 and 278.72

Calculator

Solution

The fourth proportional to 338.86, 507.38 and 278.72 is: 417.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.86 : 507.38 = 278.72 : x
  2. Step 2: Convert to fraction form
    338.86/507.38 = 278.72/x
  3. Step 3: Cross multiply
    338.86x = 507.38 × 278.72
  4. Step 4: Simplify right side
    338.86x = 141,413.02
  5. Step 5: Solve for x
    x = 141,413.02/338.86
  6. Step 6: Final answer
    x = 417.32

Related Problems

Find fourth proportional to 169.43, 253.69 and 139.36
Half scale
Find fourth proportional to 677.72, 1,014.75 and 557.43
Double scale
Find fourth proportional to 339.86, 508.87 and 279.72
Similar ratio
Find fourth proportional to 508.29, 761.06 and 418.07
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.