Home / 326.88-489.36-278.40

Finding the Fourth Proportional to 326.88, 489.36 and 278.40

Calculator

Solution

The fourth proportional to 326.88, 489.36 and 278.40 is: 416.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    326.88 : 489.36 = 278.40 : x
  2. Step 2: Convert to fraction form
    326.88/489.36 = 278.40/x
  3. Step 3: Cross multiply
    326.88x = 489.36 × 278.40
  4. Step 4: Simplify right side
    326.88x = 136,237.82
  5. Step 5: Solve for x
    x = 136,237.82/326.88
  6. Step 6: Final answer
    x = 416.78

Related Problems

Find fourth proportional to 163.44, 244.68 and 139.20
Half scale
Find fourth proportional to 653.76, 978.72 and 556.80
Double scale
Find fourth proportional to 327.88, 490.86 and 279.40
Similar ratio
Find fourth proportional to 490.32, 734.04 and 417.60
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.