Home / 270.40-405.56-78

Finding the Fourth Proportional to 270.40, 405.56 and 78

Calculator

Solution

The fourth proportional to 270.40, 405.56 and 78 is: 116.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    270.40 : 405.56 = 78 : x
  2. Step 2: Convert to fraction form
    270.40/405.56 = 78/x
  3. Step 3: Cross multiply
    270.40x = 405.56 × 78
  4. Step 4: Simplify right side
    270.40x = 31,633.68
  5. Step 5: Solve for x
    x = 31,633.68/270.40
  6. Step 6: Final answer
    x = 116.99

Related Problems

Find fourth proportional to 135.20, 202.78 and 39
Half scale
Find fourth proportional to 540.80, 811.12 and 156
Double scale
Find fourth proportional to 271.40, 407.06 and 79
Similar ratio
Find fourth proportional to 405.60, 608.34 and 117
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.