Home / 826.15-1,239.35-278.20

Finding the Fourth Proportional to 826.15, 1,239.35 and 278.20

Calculator

Solution

The fourth proportional to 826.15, 1,239.35 and 278.20 is: 417.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    826.15 : 1,239.35 = 278.20 : x
  2. Step 2: Convert to fraction form
    826.15/1,239.35 = 278.20/x
  3. Step 3: Cross multiply
    826.15x = 1,239.35 × 278.20
  4. Step 4: Simplify right side
    826.15x = 344,785.78
  5. Step 5: Solve for x
    x = 344,785.78/826.15
  6. Step 6: Final answer
    x = 417.34

Related Problems

Find fourth proportional to 413.08, 619.67 and 139.10
Half scale
Find fourth proportional to 1,652.30, 2,478.69 and 556.40
Double scale
Find fourth proportional to 827.15, 1,240.85 and 279.20
Similar ratio
Find fourth proportional to 1,239.23, 1,859.02 and 417.30
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.