Answer:
6.57, 6.38, 6.125, 6.057, 6.03, 6.01
Step 1. Simplify

to

Step 2. Simplify

to

Step 3. Simplify

to

Step 4. Cancel

on both sides
Step 5. Multiply both sides by

(the LCM of

)
Step 6. Expand
Step 7. Subtract

from both sides
Step 8. Simplify

to

Step 9. Multiply both sides by


Done! :) Hope this helps! :)
Answer:
41
Step-by-step explanation:
first you do 21×2 and that's literally it
You need to do 120-60=60 and that means he only needs $60.
Answer:
20 hours
Step-by-step explanation:
We can work easier if we think in terms of an hour
the first equation that we can write is
A + B = 1/4 (its meaning is that in an hour A and B fill 1/4 of the cistern)
the second equation we can write is
A + C = 1/5 (its meaning is that in an hour A and C fill 1/5 of the cistern)
the third equation that we can write is
B = 2C (its meaning is that in an hour B fill 2 times C the cistern)
now we can substitute the value of B in the first two equations
A + 2C = 1/4
A + C = 1/5
A = 1/5 - C
1/5 - C + 2C = 1/4
C = 1/4 -1/5
C = (5-4)/20
C = 1/20 (this means that in an hour C will fill 1/20 of the cistern, so it takes 20 hours to fill the entire cistern)
A = 1/5 - 1/20
A = (4-1)/20 = 3/20
B = 1/20 *2 = 1/10