Home / 355.78-491.43-257.91

Finding the Fourth Proportional to 355.78, 491.43 and 257.91

Calculator

Solution

The fourth proportional to 355.78, 491.43 and 257.91 is: 356.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    355.78 : 491.43 = 257.91 : x
  2. Step 2: Convert to fraction form
    355.78/491.43 = 257.91/x
  3. Step 3: Cross multiply
    355.78x = 491.43 × 257.91
  4. Step 4: Simplify right side
    355.78x = 126,744.71
  5. Step 5: Solve for x
    x = 126,744.71/355.78
  6. Step 6: Final answer
    x = 356.24

Related Problems

Find fourth proportional to 177.89, 245.72 and 128.96
Half scale
Find fourth proportional to 711.56, 982.86 and 515.82
Double scale
Find fourth proportional to 356.78, 492.81 and 258.91
Similar ratio
Find fourth proportional to 533.67, 737.15 and 386.87
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.