Mathcounts problems?

Question

Can someone show me how to do these?

A convex pentagon has interior angles with measures x + 1, 2x, 3x, 4x and 5x-1 degrees. What is the measure of the largest angle?

A groundskeeper must buy bags of fertilizer. Each bag treats 10,000 square feet of ground and costs $27. The groundskeeper can buy only whole bags of fertilizer. How much will it cost to buy the least number of bags necessary to treat 6000 square yards of ground?

On Claudia's bday in 2004, her age was four times her brother's age on that day. On her birthday in 2005, her age was three times her brother's age on that day. In what year will Claudia's age, on her birthday, be twice her brother's age on that day?

In a group of cows and chickens, the number of legs is 14 more than twice the number of heads. How many cows are there in the group?

Thanks!

Answer 1

pentagon: 15x =540

x=36

5x -1=179

fertilizer: 6000sq yd =54000 sq ft

54000/10000 =5.4

6 x $27 =$162

4x + 1 = 3(x+1)

4x +1=3x +3

x=2

In 2004, Claudia was 8; her brother was 2

In 2005, Claudia was 9; her brother was 3

she is six years older and when he is 6, she will be 12.

In 2008, Claudia is 12; her brother is 6.

x=number of cows, y=number of chickens

4x +2y =2(x+y) +14

4x +2y =2x +2y +14

2x=14

x= 7 cows