Home / 1,978.59-2,730-1,315.80

Finding the Fourth Proportional to 1,978.59, 2,730 and 1,315.80

Calculator

Solution

The fourth proportional to 1,978.59, 2,730 and 1,315.80 is: 1,815.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,978.59 : 2,730 = 1,315.80 : x
  2. Step 2: Convert to fraction form
    1,978.59/2,730 = 1,315.80/x
  3. Step 3: Cross multiply
    1,978.59x = 2,730 × 1,315.80
  4. Step 4: Simplify right side
    1,978.59x = 3,592,134
  5. Step 5: Solve for x
    x = 3,592,134/1,978.59
  6. Step 6: Final answer
    x = 1,815.50

Related Problems

Find fourth proportional to 989.30, 1,365 and 657.90
Half scale
Find fourth proportional to 3,957.18, 5,460 and 2,631.60
Double scale
Find fourth proportional to 1,979.59, 2,731.38 and 1,316.80
Similar ratio
Find fourth proportional to 2,967.89, 4,095 and 1,973.70
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.