Home / 288.81-398.79-223.20

Finding the Fourth Proportional to 288.81, 398.79 and 223.20

Calculator

Solution

The fourth proportional to 288.81, 398.79 and 223.20 is: 308.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    288.81 : 398.79 = 223.20 : x
  2. Step 2: Convert to fraction form
    288.81/398.79 = 223.20/x
  3. Step 3: Cross multiply
    288.81x = 398.79 × 223.20
  4. Step 4: Simplify right side
    288.81x = 89,009.93
  5. Step 5: Solve for x
    x = 89,009.93/288.81
  6. Step 6: Final answer
    x = 308.20

Related Problems

Find fourth proportional to 144.41, 199.40 and 111.60
Half scale
Find fourth proportional to 577.62, 797.58 and 446.40
Double scale
Find fourth proportional to 289.81, 400.17 and 224.20
Similar ratio
Find fourth proportional to 433.22, 598.19 and 334.80
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.