Given:
Either has a school certificate or diploma or even both = 20 people
Having school certificates = 14
Having diplomas = 11
To find:
The number of people who have a school certificate only.
Solution:
Let A be the set of people who have school certificates and B be the set of people who have diplomas.
According to the given information, we have



We know that,



Subtract both sides by 25.



We need to find the number of people who have a school certificate only, i.e.
.



Therefore, 9 people have a school certificate only.
It’s simple. The volume of a sphere is V=4/3πr^3.. so you will convert the mm to m okay?? 10mm=1cm .. so do your conversion from here then when you get the radius then you will substitute it into the volume where r is the radius.. so for the first one l changed mm to cm so.. radius is 4cm then l substitute it into the formula so l got 270 after rounding it to the nearest tenth.. pi=22/7 bear in mind. So do the same for the other one
Answer:
Step-by-step explanation:
2a-7+15-5a
2a-5a-7+15
-3a+8