Keiko's Coffee Shop makes a blend that is a mixture of two types of coffee. Type A coffee cost Keiko $4.15 per pound, and type B coffee costs $5.25 per pound. This month's blend used four times as many pounds of type B coffee as type A, for a total cost of $980.85. How many pounds of type A coffee were used?

39 pounds of type A coffee were used.

Step-by-step explanation:

Given: Cost of type A coffee is $4.15 per pound and cost of type B coffee is $5.25 per pound. Also, blend used four times as many pounds of type B coffee as type A.

To find: How many pounds of type A coffee were used.

Let be the number of pounds of type A coffee and be the number of pounds of type B coffee.

Then, according to question,

and

Substituting in , we get

⇒

⇒

⇒

⇒

Therefore, 39 pounds of type A coffee were used.

Step-by-step explanation:

1] the minimum number of arcs in any strongly connected digraph with n vertices is 'n' . the graph look like a cycle

the graph is in the attached file

in a directed cycle we have strongly connected graph since we can reach any vertax from any vertax, it has minimum arc which is 'n'

since if we use less than n vertax then the given graph has atmost one tree which is not strongly connected graph.

2] the maximum distance between two vertax is 5 which from veratx 1 to vertax 6 distance is 5

1----->2------->3--------->4------->5-------->6

if we use cycle of n node then the maximum distance between two vertax is n-1