I am currently read a book, and there is something that I'm struggling to understand (I have weak background in math):
Anya has 3 pounds of tofu, Betty has twice as much tofu as Anya, Carmen has 5 pounds more tofu than Betty, Deirdre has three times the tofu that Carmen has. In arithmetical it stands like that:
A= 3 B= 2XA C= B+5 D= 3XC
Now for my problem of understanding, he writes:
We can combine these four statements into one statement by substitution and then finally perform the additions and multiplications:
D= 3XC D= 3X(B+5) D= 3X((2Xa)+5) D= 3X((2X3)+5) D= 33
My questions are:
- Why is the
Dstand for all of the letters before.
- What is the substitution he talks about.
- How he gets the number 33 at the end ?
I would like to get some background basic information about it.