Let nails 7/pound=N1
nails 3/pound=N2
let N1=x
N2=6
then total=x+6
7x+6*3=(x+6)*4
7x+18=4x+24
3x=6
x=2
so 2 pounds on Nails costing 7/pound must be added
X≥

Distribute and then solve.
Answer:
Hi hope you have a wonderful and blessed day!!!!
Step-by-step explanation:
Use PEMDAS. 20/(4*5)=1
Multiplication before dividion
Answer:
104 miles
Step-by-step explanation:
52/2.5 = 20.8
20.8 miles = 1 inch
20.8 x 5
104 miles = 5 inches