Respuesta :
Answer:
31/40 has to be added to the sum of 5/8 and 8/5 to get 3.
Step-by-step explanation:
Solve this equation: 5/8 + 8/5 + f = 3, where f is the number that has to be added to the sum of 5/8 and 8/5.
The LCD of 5/8 and 8/5 is 40; thus, 5/8 + 8/5 = 25/40 + 64/40 = 89/40.
Then 89/40 + f = 120/40 (where 120/40 is equivalent to 3).
Subtracting 89/40 from both sides yields the desired result:
f = (120 - 89)/40 = 31/40
31/40 has to be added to the sum of 5/8 and 8/5 to get 3.
Answer:
[tex]\frac{31}{40}[/tex]
Step-by-step explanation:
let the unknown be x
[tex]\frac{5}{8} + \frac{8}{5} + x =3[/tex]
[tex]\frac{25+64+40x}{40} = 3[/tex]
cross multiply
25 + 64 + 40x = 3 × 40
89 + 40x = 120
collect like terms
40x = 120 - 89
40x = 31
divide both sides by 40
x = [tex]\frac{31}{40}[/tex]
therefore, [tex]\frac{31}{40}[/tex] has to be added to the sum of 5/8 and 8/5 to get 3