Answer:
7
Step-by-step explanation:
Formula of joint variation : [tex]z = kxy[/tex]
To Calculate k
Width(x)= 7
Height(y) = 12
Volume(z) = 420
Substitute the values in the formula
[tex]420 = k(7)(12)[/tex]
[tex]\frac{420}{7 \times 12} = k[/tex]
[tex]5= k[/tex]
Now , to find the missing height
Substitute width = x = 15
Height = ?
Volume = z = 525
Substitute the values in the formula :
[tex]525 = 5(15)y[/tex]
[tex]\frac{525}{5 \times 15}= y[/tex]
[tex]7= y[/tex]
So, the missing value is 7 .
