I need help to learn how to solve the following problem:

If 6t+7a
_______ =t
4
then what is 4t in terms of a?

6t + 7a =4t

2t = -7a

so 4t = -14a

Please answer the followin:

Four numbers have mean of 6.5. What is their sum?

Please answer the following:

The Junior Girls waterpolo team at Awarua college scored a mean of 11.25 points per game last season. Altogether they played sixteen games. How many points did the team score altogether?

PLease answer the following:

Two brotheres have a mean weight of 48 g. If one brothers weight 51 g, what does the other one weight?

(SHOW ALL THE WORKINGS)

Answer the following:

Wei-Li weighed some oranges. The mean weight was 345 g. The total weight was 2070 g. How many oranges did she weight?

(SHOW ALL THE WORKINGS)