Subtracting + sets - math problems

Number of problems found: 6

Ten pupils
10 pupils came to the art group. 8 pupils painted with watercolors and 9 pupils painted with ink, each pupil painted with ink or watercolors. How many pupils painted water and ink at the same time?
The Hotel
The Holiday Hotel has the same number of rooms on each floor. Rooms are numbered with natural numbers sequentially from the first floor, no number is omitted, and each room has a different number. Three tourists arrived at the hotel. The first one was in
Toy store
In the toy department of store was exposed 28 dolls. 19 dolls were blondes or could speak. 12 dolls were blondes, 14 could speak. How many blondes could speak in the toy department? How many blondes could not speak?
Water colors
Painting workshop attend 10 students. Eight students painted water colors and nine painted with tempera colors. How many students painted water colors and tempera at the same time?
Buffet
In the school buffet were 30 children. 21 children bought sandwiches and 15 children bought lemonade. Four children did not buy anything. How many children bought lemonade and sandwiche?
Intersect and conjuction
Let U={1,2,3,4,5,6} A={1,3,5} B={2,4,6} C={3,6} Find the following. 1. )AUB 2. )A'UB'

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