Lets x is price of noble fir trees and y - is price for douglas fir trees
students got 5x+3y=420$ on friday
and 12x+9y=1080
now we need just solve the system of equations
5x+3y=420 - multiply by 3
12x+9y=1080
15x+9y=1260
12x+9y=1080
substract second equation from first
15x-12x=1260-1080
3x=180
x=60$ - the price of noble fir trees
put value x=60 in first equation 5x+3y=420
5*60+3y=420
300+3y=420
3y=120
y=40$ - price of Douglas fir trees
Answer: Noble fir trees cost $60 and Douglas fir trees cost $40
Hello,
We have to use this relation : 
He we have :
Answer:
1. D) 1 9/20
2. B) 7/12
4. D) $50.00
Step-by-step explanation:
The working is as follows :
1. Mrs. Lang bought 3/4 pound of red grapes and 7/10 pound of green grapes. To find out how many are in total we have to add both values total.
3/4 + 7/10
The LCM of 4 and 10 is 20.
3/4 * 5 = 15/20
7/10 * 2 = 14/20
15/20 + 14/20 = 29/20 = 1 9/20
2. 1/3 + 1/4
The LCM of 3 and 4 is 12
1/3 * 4 = 4/12
1/4 * 3 = 3/12
4/12 + 3/12 = 7/12
4. Sharon spent 2/3 of her clothing allowance; she was given $75. All we have to do is find 2/3 of $25 :
2/3 * $75 = $50.00
Answer:
8cm
Step-by-step explanation:
2 cm =1 ft so if i multiply it by 4ft, and remember 2 cm =1 ft so 2×4=8
8cm
The area of the pizza is <span>20.37.
Hope this helps ^^</span>
