Home / 443.60-665.40-280.80

Finding the Fourth Proportional to 443.60, 665.40 and 280.80

Calculator

Solution

The fourth proportional to 443.60, 665.40 and 280.80 is: 421.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    443.60 : 665.40 = 280.80 : x
  2. Step 2: Convert to fraction form
    443.60/665.40 = 280.80/x
  3. Step 3: Cross multiply
    443.60x = 665.40 × 280.80
  4. Step 4: Simplify right side
    443.60x = 186,844.32
  5. Step 5: Solve for x
    x = 186,844.32/443.60
  6. Step 6: Final answer
    x = 421.20

Related Problems

Find fourth proportional to 221.80, 332.70 and 140.40
Half scale
Find fourth proportional to 887.20, 1,330.80 and 561.60
Double scale
Find fourth proportional to 444.60, 666.90 and 281.80
Similar ratio
Find fourth proportional to 665.40, 998.10 and 421.20
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.