Home / 386.78-533.25-303.75

Finding the Fourth Proportional to 386.78, 533.25 and 303.75

Calculator

Solution

The fourth proportional to 386.78, 533.25 and 303.75 is: 418.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.78 : 533.25 = 303.75 : x
  2. Step 2: Convert to fraction form
    386.78/533.25 = 303.75/x
  3. Step 3: Cross multiply
    386.78x = 533.25 × 303.75
  4. Step 4: Simplify right side
    386.78x = 161,974.69
  5. Step 5: Solve for x
    x = 161,974.69/386.78
  6. Step 6: Final answer
    x = 418.78

Related Problems

Find fourth proportional to 193.39, 266.63 and 151.88
Half scale
Find fourth proportional to 773.55, 1,066.50 and 607.50
Double scale
Find fourth proportional to 387.78, 534.63 and 304.75
Similar ratio
Find fourth proportional to 580.16, 799.88 and 455.63
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.