Answer:
![(1)/(10)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/aepwrh3e943x7efcio9xavy7vrbdkbcn1i.png)
Explanation:
Red
![(2)/(5)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/5jm6oitkd3lorjig5jfw17qliocw7lqrpz.png)
blue
![(1)/(8)](https://img.qammunity.org/2021/formulas/mathematics/high-school/hcxhwcun3tdhxxrdgcla5lb39my4jlljjt.png)
green
![(3)/(8)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/x2q5g60h9zz3zovzkcti6og4swfi4jks4o.png)
first, make denominators same.
*The common LCM we choose is 40*
RED
![(2)/(5) * 8 = (16)/(40)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/xv6rw13uzkibhtnrwg428chrn179ifhto1.png)
BLUE
![(1)/(8) * 5 = (5)/(40)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/mnanjjog5ya0d9e41otjwnq2qak03jknsw.png)
GREEN
![(3)/(8) * 5 = (15)/(40)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/8pi6x26wgtff4ie7qo82rkeh0fq806fc7c.png)
Yellow marble:-
RED+GREEN+BLUE =
![(16)/(40) + (5)/(40) + (15)/(40) = (36)/(40)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/xez61ygcarld6p5reglkdpjbosr2yzlq91.png)
Yellow marble = total marbles-sum of other marble colours
*note that the total no. marbles are 40*
![(40)/(40) - (36)/(40) = (4)/(40)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/qf8n50d4oqrn8pqcruzkrv1m9cg2y74nza.png)
*you can leave it in this form or you can simplify it*
![(4)/(40) or (1)/(10)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/e7xiysgwdk0ly3o2rdwmpk70nxs1px53fg.png)