Home / 475.80-656.40-289.20

Finding the Fourth Proportional to 475.80, 656.40 and 289.20

Calculator

Solution

The fourth proportional to 475.80, 656.40 and 289.20 is: 398.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    475.80 : 656.40 = 289.20 : x
  2. Step 2: Convert to fraction form
    475.80/656.40 = 289.20/x
  3. Step 3: Cross multiply
    475.80x = 656.40 × 289.20
  4. Step 4: Simplify right side
    475.80x = 189,830.88
  5. Step 5: Solve for x
    x = 189,830.88/475.80
  6. Step 6: Final answer
    x = 398.97

Related Problems

Find fourth proportional to 237.90, 328.20 and 144.60
Half scale
Find fourth proportional to 951.60, 1,312.80 and 578.40
Double scale
Find fourth proportional to 476.80, 657.78 and 290.20
Similar ratio
Find fourth proportional to 713.70, 984.60 and 433.80
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.