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Can you think of examples where 2 + 2 does NOT equal 4?
Like, for example, 2 gallons plus 2 quarts does NOT equal 4 gallons.
- Jeffrey KLv 72 months ago
You can not add different units together. It's not that 2+2 doesn't equal 4. It is just that gallons plus quarts can not be added.
Here are some mathematical instances when 2+2 is not 4.In base 3: 2+2 = 11In base 4: 2+2 = 10If two vectors of length 2 are added, the sum will be less than 4.
In algebra, 2X + 2 is not 4 or 4X. They can not be added.
In Relativity, a speed of 2 hundred thousand km per sec plus 2 hundred thousand km per sec is not 4 hundred thousand km per sec. It is less. You must use the Relativistic velocity addition formula.
- JimLv 72 months ago
A change in number base, such as base 3 or base 4
A change in units like 2 gals + 2 qts
A change in systems such as 2 gals + 2 liters
In human terms such as 2 couples having babies.
Etc. for like a million (exaggeration) different ways.
- llafferLv 72 months ago
in base 4:
2₄ + 2₄ = 10₄
- UserLv 72 months ago
You're using different units, which is sort of cheating.
Another way of doing this is adding groups, collective nouns and the like.
Consider: 2 flocks of birds (of the same species) combine with 2 flocks of birds (again: of the same species)
2 flocks + 2 flocks = 1 flock
There is a merger between two companies, the result being the forming of a new company
1 company + 1 company = 1 company
One company purchases another company and integrates it into the parent company.
company A + company B = company A
(many variations on the theme)
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- billrussell42Lv 72 months ago
your example is bad, you cannot add unlike terms.
8 qt + 2 qt = 10 qt
vectors are a real example. A force of 2 N east plus a force of 2 E add to 2.8 N NE
then there is the classic, where everything is rounded to 1 place
2.4+2.4 = 4.8 when rounded is
2 + 2 = 5
or speeds approaching light speed.
relativistic speed additionS = (v+u)/(1+vu/c²)
let u and v be 2e8 m/s
S = 4e8 / (1 + 4/9) = 2.7 m/s
so 2e8 plus 2e8 = 2.7e8 m/s
of course, non of these are actually 2 + 2 ≠ 4