<span>Twice the sum of a number and 3 = 2(n + 3) </span><span>three times the difference of the number and 3 = 3(n - 3) so </span><span>Twice the sum of a number and 3 is equal to three times the difference of the number and 3: </span>2(n + 3) = 3(n - 3) 2n + 6 = 3n - 9 n = 15
Explanation: > Twice translated to mathematical terms is x 2.
> Sum is the result of the operation addition.
> Variables stand for an unnamed or unknown number(s). 'A number' indicates that we don't know what number it is exactly, therefore it'll be represented as a variable.
> Equal to indicates the equality sign, thus making this an equation.
> Three times = x 3
> Difference is the result of the operation subtraction.
> Multiplication goes before addition and subtraction in the PEMDAS rule, however parenthesis comes before multiplication. The x + 3 and x - 3 are in parentheses because we need the sum and difference between x and 3 first before multiplying it.
First find out how much the 4 volleyball nets are by using 4*28 which would equal to 112. Now subtract 112 from 250 and that leaves you with 138. Then you divide 138 by 7 which will give you about 19.7 which you need to take all decimals out since it isn’t an whole number. The gym teacher can only buy 19 volleyballs.
