Which number does not belong in the following series? (2)

Which one of the numbers does not belong in the following series?
3, 4, 8, 9, 10, 18, 19, 38

You can check your solutions here

Plants

“How many plant species are there?” It was of course my old friend professor Brainstrain who asked this. His nephew looked bewildered.
“10? No, more”, he thought. Then he asked: “over a hundred, maybe?”
“Many more,” the professor asked with a smile.
He went on:
“In the following addition, every digit had been replaced with a letter. Find the original sum.

You can check your solutions here

Which item does not belong in the following series? (1)

Which one of the numbers does not belong in the following series?
E, D, I, H, J, O, N, U

This kind of questions is one of several types found in the Wechsler IQ test. Unfortunately, one of the questions as I found it online has two answers.

You can check your solutions here

Apologies for not publishing a puzzle last Friday.