30 percent change is the answer
A typewriter costing $75.00 marked up 40% on cost M = 40 and S = 105
Step-by-step explanation:
Approach: If four numbers a, b, c and d are in proportion then a:b = c:d. The solution is to sort the four numbers and pair up the first 2 together and the last 2 together and check their ratios this is because, in order for them to be in proportion, the product of means has to be equal to the product of extremes.
Answer:4 2/7 - 6/7 = 24/
7
= 3 3/
7
≅ 3.4285714
Step-by-step explanation: