# Common among the uncommon

What is common among the seemingly uncommmon among the following:

1. One of the types of human blood groups

2. Grading representation in schools

3. Part of alternate representation for Like/ up vote

4. Mother of all numerical operations, well, considered in a way

5. That type of growth usually goes up and right

?

• I was thinking of "a positive(+)" but can't seem to meet 4th requirement. Aug 29, 2017 at 15:16
• Good thought process @Firelord, you should have posted your answer ! Aug 29, 2017 at 15:31
• Well I'm new here and didn't know one can post partial answers here too. I'll try next time. Aug 29, 2017 at 15:32

The common factor is

+ (the plus sign)

1. Blood type

For the gene A, B, or O, you can have a positive (+) or negative (-) type.

For each letter grade (A, B, C, etc.) some schools assign plus or minus for granularity. For example, A+ > A > A- > B+ > B, and so on.

3. Like/upvote

An upvote are sometimes referred to as +1 (plus one vote).

4. Operators

Addition (X + Y) is one of the first mathematical operations that people learn. Subtraction is negative addition, and multiplication is repeated addition.

5. Growth

A monotonic function with a positive rate moves up and right. For example, in the function y=2x, the rate is +2 (positive); and when you visualize the graph, the value of y moves up as you move right along the x axis.

• Good one @Mike Q, you got it fully correct ! Aug 29, 2017 at 15:30
• @Dexter Maybe not, it's easy to find out in an instant... Aug 29, 2017 at 16:05

The pattern is:

The first 5 letters of the alphabet

1)

A is a blood group

2)

B is a grade that is given in schools

3)

Unsure

4)

D for differentials/derivatives

5)

E for exponential graph - which is a graph that is always growing... i.e. up and to the right

• Nice try, @Dexter. Liked the variants in explaning the clues ! Aug 29, 2017 at 15:32