11. Six times a certain number less 31 is the same as 10 subtracted from Ehree times the number. Write the equation and find the number.

Step-by-step explanation:

x       - a certain number

6x  -  - six times the number

6x-31    - six times the number less 31

3x        - three times the number

3x-10    -  10 subtracted from  three times the number

so the equation:

6x - 31 = 3x - 10

    +31       +31

 6x  =  3x + 21

 -3x     - 3x

3x  = 21  

 ÷3     ÷3

 x = 7

Check:  6•7-31=42-31=11;   3•7-10=21-10=11  

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.

4 candies

step-by-step explanation:

7 x 28 = 196

200 - 196 = 4 candies remaining.