`a, 7/3 : 14/15 + 9/4`
` = 7/3 . 15/14 + 9/4`
` = 5/2 + 9/4`
` = 10/4 + 9/4 = 19/4`
b, `15 3/7 - (8/9 + 7 3/7 )`
` = 15 3/7 - 8/9 - 7 3/7`
` = 8 - 8/9`
` = 64/9`
c,`|-5/12| + (-2/3)^2. (20% - 1,2)`
` = 5/12 + 4/9 . (0,2 - 1,2)`
` = 5/12 + 4/9 . (-1)`
` = 5/12 + (-4/9)`
` = -1/36`
d, `5/9 . 7/13 - 30/23 + 6/9 . 5/13 + 7/23`
= `5/9 . 7/13 + 6/13 . 5/9 - (30/23 - 7/23)`
= `5/9 . (7/13 + 6/13) - 1`
= `5/9 . 1 - 1`
= `5/9 - 1`
= `-4/9`
e, `2022 - 40% + 3/5 . (-1)^2021`
= `2022 - 2/5 + 3/5 . (-1)`
= `2022 - 2/5 - 3/5`
= `2022 - (2/5 + 3/5) = 2022 - 1 = 2021`
f. `-8/5 . 4/11 + -8/15 . 7/11 + 3 8/15`
` = (-8/15) . 3 . 4/11 + -8/15 . 7/11 + 53/15`
` = (-8/15) . (3 . 4/11 + 7/11) + 53/15`
` = (-8/15) . 19/11 + 53/15`
` = -152/165 + 53/15`
` = 431/165`
