Answer:
Total cost=$25
Step-by-step explanation:
We can derive two expressions as follows;
Total cost for the First shipping company=Medium box charges+total additional charges
where;
Medium box charges=$20
Total additional charges=Charges per pound×number of additional pounds (n)
Total additional charges=1×n=n
replacing;
Total cost for the First shipping company=20+n....equation 1
Total cost for the second shipping company=Medium box charges+total additional charges
where;
Medium box charges=$15
Total additional charges=Charges per pound×number of additional pounds (n)
Total additional charges=2×n=2 n
replacing;
Total cost for the First shipping company=15+2 n....equation 2
Equating equation 1 and equation 2
15+2 n=20+n
2 n-n=20-15
n=5
Replace the value for n in equation 2
Total cost for the First shipping company=15+2 n....equation 2
Total cost=15+(2×5)=$25
Answer:
59
Step-by-step explanation:
b^3 is 27
2(27) is 54
54+5 is 59
if u mean (2b)^3 then 2b is 6
6^3 is 216
plus 5 is 221
Ni : Zn: Cu = 7:2:9 =7x : 2x : 9x
7x+2x+9x = 3.8
18x=3.8
x=3.8/18=1.9/9≈0.21
Ni: 7x=7*0.21=1.47 ≈1.5 kg
Zn: 2x=2*0.21=0.42≈0.4 kg
Cu: 9x=9*0.21=1.89 ≈1.9 kg
Check 1.5+0.4+1.9 =3.8 True