Home / 280-386.40-263.80

Finding the Fourth Proportional to 280, 386.40 and 263.80

Calculator

Solution

The fourth proportional to 280, 386.40 and 263.80 is: 364.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    280 : 386.40 = 263.80 : x
  2. Step 2: Convert to fraction form
    280/386.40 = 263.80/x
  3. Step 3: Cross multiply
    280x = 386.40 × 263.80
  4. Step 4: Simplify right side
    280x = 101,932.32
  5. Step 5: Solve for x
    x = 101,932.32/280
  6. Step 6: Final answer
    x = 364.04

Related Problems

Find fourth proportional to 140, 193.20 and 131.90
Half scale
Find fourth proportional to 560, 772.80 and 527.60
Double scale
Find fourth proportional to 281, 387.78 and 264.80
Similar ratio
Find fourth proportional to 420, 579.60 and 395.70
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.