Math Help. (2 questions)

Can you help me with these.

1.) The mean of ten numbers is 86. One of the numbers is 68, what is the mean of the other 9 numbers?

2.) BEFL sells fuel to different gas stations in Belize City in the ration of 4:5:6 as shown below.

Type of Fuel / Ratio / Gals. Fuel p. Week
Diesel - 4 / ?
Regular - 6 / ?
Kerosene - 5 / 960,000 gals


a.) How many gallons sell per week all together?
b.) Regular gasoline sells at $11.25 per gallon (thats true where i live). Calculate the amount BEFL makes from selling this fuel.
c.) What is the percent of the total fuel is kerosene fuel sold in the gas stations per week.

1) mean of ten numbers = 86.
So, 86 per head.
one is gone with 68.
So, it has left 86 - 68 = 18 behind.
So, 18 / 9 = 2 more for other 9
So, the average for the rest is 86+2=88

Another solution: 86 x 10 = 860.
860 - 68 = 792.
so, 792 / 9 = 88.

2) a. total ratio = 4+6+5 =15.
5 = 960,000,
1 = 960,000 / 5
15 = 960,000 x 15 / 5 = 2,880,000 Gals. Fuel

b. 5 = 960,000
1 = 960,000 / 5
6 = 960,000 x 6 /5 = 1,152,000 Gal Regular gasoline
so, Total price of Regular Gasoline = 1,152,000 x $11.25 = $12,960,000

c. total ration = 4+6+5 = 15.
if total is 15, then Kerosene = 5
if total is 1, then Kerosene = 5 / 15
if total is 100, then Kerosene = 5 x 100 / 15 = 33.33%

let the 10 numbers be a to j
Therefore, (a+b+c+d+e+f+g+h+i+j)/10 = 86
Multiply both sides by 10, we get a+b+c+d+e+f+g+h+i+j = 860
Let say a=68. So 68+b+c+d+e+f+g+h+i+j= 860 (subtract 68 from both sides) => b+c+d+e+f+g+h+i+j = 792
Divide both sides by 9 , as to get mean of 9 numbers therefore (b+c+d+e+f+g+h+i+j)/9 = 88
So mean is 88