Master Jia makes three tables and nine chairs a day, and one master makes two tables and seven chairs a day. After 20 days of cooperation, he made 134 and asked how many desks and chairs there were.

Analysis: (1), Master A makes 9-3 = 6 more chairs than tables every day;

(2) Master B makes 7-2=5 more chairs than tables every day;

(3) Now imagine that the two of them will make watches in 20 days, and they should make 20*(2+3)= 100 sheets;

(4) But actually the number of desks and chairs is 134. The extra 34 figures should be caused by Master A and Master B making chairs instead of tables within a certain number of days.

(5) Now the problem becomes that A does it six times a day, and B does it five times a day, making a total of 34 times. Ask A how many days and B how many days; Because an integer is needed, 34=24+ 10=4*6+2*5, so A did it for 4 days and B did it for 2 days.

(6) Back to the original question, I know that A has been a chair for four days and B has been a chair for two days, so the number of chairs =4*9+2*7=50.

The number of tables is 84.