Home / 330.89-457.14-257.78

Finding the Fourth Proportional to 330.89, 457.14 and 257.78

Calculator

Solution

The fourth proportional to 330.89, 457.14 and 257.78 is: 356.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    330.89 : 457.14 = 257.78 : x
  2. Step 2: Convert to fraction form
    330.89/457.14 = 257.78/x
  3. Step 3: Cross multiply
    330.89x = 457.14 × 257.78
  4. Step 4: Simplify right side
    330.89x = 117,843.66
  5. Step 5: Solve for x
    x = 117,843.66/330.89
  6. Step 6: Final answer
    x = 356.15

Related Problems

Find fourth proportional to 165.44, 228.57 and 128.89
Half scale
Find fourth proportional to 661.77, 914.29 and 515.57
Double scale
Find fourth proportional to 331.89, 458.53 and 258.78
Similar ratio
Find fourth proportional to 496.33, 685.72 and 386.67
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.