Question

1. Выпишите все неправильные дроби: 8/17; 9/5; 7/7; 35/98; 120/120; 7/9; 12/40. 2. Вычислите: а) 5/7-1/2; б) 7/8+3/4; в) 5/6-3/10; г) 1/5-2/3+3/10+3/5. 3. Сравните числа: а) 15/19 и 12/19; б) 4/5 и 17/10; в) 8/9 и 5/5; г) 1 и 21/16; д) 3/3 и 55/55; е) 35/45 и 35/55. 4. Сократите дробь: а) (15 ∙ 38 ∙7)/(19 ∙ 21 ∙ 5); б) (9∙12-4∙12)/60; в) (12ac^2 d)/24cba; г) (21acb^2-21bca^2)/(7a^2 b^2 (b-a)); 5.1. Найдите периметр треугольника ABC, если известно, что сторона AB=7/15 м, сторона BC=17/90 м, а сторона AC меньше суммы сторон AB и BC на 1/5 м. 5.2. Найдите хотя бы одну дробь, которая больше 3/4, но меньше 4/5.

Answer 1

1)9/5;
2)а)5/7-1/2=1/7
   б)7/8+3/4=13/8(выделяя целую часть получим :одну целую пять восьмых)
   в)5/6-3/10=1/3
   г)1/5-2/3+3/10+3/5=(-7/15)+3/10=(-1/6)+3/5=13/30
3)а)>;б)<;в)<;г)<;д)=;е)>;
4)а)-2;б)-1;в)-сd/b ;г)-
5)10/9
   

Answer 2

Sure! Let's solve the math problems step by step:

1. Listing improper fractions: - 8/17 - 9/5 - 7/7 - 35/98 - 120/120 - 7/9 - 12/40

2. Calculating expressions: a) 5/7 - 1/2 = (5 * 2 - 1 * 7) / (7 * 2) = 3/14 b) 7/8 + 3/4 = (7 * 4 + 3 * 8) / (8 * 4) = 41/32 c) 5/6 - 3/10 = (5 * 10 - 3 * 6) / (6 * 10) = 17/30 d) 1/5 - 2/3 + 3/10 + 3/5 = (1 * 30 - 2 * 10 + 3 * 3 + 3 * 6) / (5 * 3) = 23/15

3. Comparing numbers: a) 15/19 and 12/19: 15/19 is greater than 12/19 b) 4/5 and 17/10: 4/5 is less than 17/10 c) 8/9 and 5/5: 8/9 is greater than 5/5 d) 1 and 21/16: 21/16 is greater than 1 e) 3/3 and 55/55: 3/3 is equal to 55/55 f) 35/45 and 35/55: 35/45 is less than 35/55

4. Simplifying fractions: a) (15 * 38 * 7) / (19 * 21 * 5) = 7980/3995 (the fraction cannot be simplified further) b) (9 * 12 - 4 * 12) / 60 = 108/60 = 9/5 c) (12ac^2 + d) / (24cba) (the fraction cannot be simplified further) d) (21acb^2 - 21bca^2) / (7a^2 + b^2 + (b - a)) (the fraction cannot be simplified further)

5.1 Finding the perimeter of triangle ABC: Given: AB = 7/15 m, BC = 17/90 m, AC is less than the sum of AB and BC by 1/5 m. AC = (AB + BC) - 1/5 = (7/15 + 17/90) - 1/5 = 19/30 - 1/5 = 7/30 m Perimeter = AB + BC + AC = 7/15 + 17/90 + 7/30 = 14/30 + 17/90 + 7/30 = 38/90 + 17/90 + 21/90 = 76/90 = 38/45 m

5.2 Finding a fraction between 3/4 and 4/5: We can find a fraction by taking the average of the two fractions: (3/4 + 4/5) / 2 = (15/20 + 16/20) / 2 = 31/40 / 2 = 31/80 Therefore, one fraction that is greater than 3/4 but less than 4/5 is 31/80.

I hope this answers your questions! Let me know if you need any further assistance.