13-[26-(-21)+（-18)]=

13-（26+21-18）=13-29=-16

RELATED INFORMATIONS

1. What is the quotient of dividing 4 out of 9 into 1 out of 9 out of 18? Is it division or not
2. 2 and 3 of 9 = 18 () = () 80
3. The results show that √ 18 - √ 9 of 2 - √ 3 of 3 + √ 6 + (√ 3-2) + √ (1 - √ 2) & sup2;
4. 20 out of 70, 15 out of 35, 42 out of 45, 21 out of 36, 33 out of 55, 26 out of 52, 50 out of 20, 28 out of 35, 81 out of 18, the simplest score is urgent! Great Xia, help! Please, thank you
5. What is the denominator x if the numerator 48 and denominator X are equal to the numerator 36 and denominator 24
6. If the size of a fraction is equal to 18 / 24, the numerator is equal to 6, and the denominator is smaller than 24, what is the fraction? The answer is 3 / 7. What's the matter?
7. For a fraction, if the numerator adds 8 and the denominator subtracts 10, its simplified value is 34. If the numerator adds 18 and the denominator adds 32, its simplified value is 12. What is this fraction______ ．
8. Find [60,72,84] (60,72,84) [18.12.24] (18.12.24)
9. ）Equal to 16 / 3 of () equal to 2 / 3 equal to () divided by 18 equal to 24 divided by ()
10. (2 √ 24 - √ 18) △ 3 + 2 √ 3 / 2
11. （1/1*4）+（1/2*5）+（1/3*6）...+（1/17*20）+（1/18*21）=?
12. 1 out of 18 + (2 out of 3 + 4 out of 21) = = = How much is it?
13. 4 + 4 + 1 / 2 * 6 / 7 / 9 / 5 of 14 -- (1 + 5 / 6 + 1 + 11 / 18)
14. 5 / 9 + 3 / 11 + 4 / 9 + 8 / 11 + 7 / 18 △ 4 + 3 / 4 × 7 / 18 (1 / 4-1 / 6) × 12 5 of 9 + 3 of 11 + 4 of 9 + 8 of 11 + 7 of 18 △ 4 + 3 of 4 × 7 of 18 (1 of 4-1 of 6) × 12 important process
15. The process of finding [6 and 5 / 3 - (8.5-1 / 3) △ 3.5] × (2 and 18 / 5 + 12 / 11)
16. 25 1 / 3 - [(20-15 3 / 4) + (13 3 / 4-17)]
17. A simple method to calculate 15 × (4 + 20)=
18. A cylindrical steel is 1 meter long and 1 cm in cross-sectional diameter. How many cubic centimeters is the volume of this steel? If each cubic centimeter of steel weighs 7.5 grams, how many kilograms does this steel weigh?
19. The radii of circle O1 and circle 02 are 3cm and 4cm respectively. Under the following conditions, the position relationship between circle O1 and circle O2 can be obtained (1) O1O2 = 8 cm (2) O1O2 = 7 cm (3) O1O2 = 5cm (4) O1O2 = 1cm (5) O1O2 = 0.5cm (6) 01 and O2 coincide
20. What is a number that is three-thirds larger, two-thirds less, divided by two, plus one-quarter equal to seven twelfth