1/2 x > 0.4x
where Robert's spending is greater than Rosa's spending.
Allowance of Rosa = Allowance of Robert
let x = allowance
Rosa : video games = 0.4(x) ; pizza = 2/5 (x)
Robert : video games = 1/2 (x) ; pizza = 0.25 (x)
let us assume that their allowance is 100 each week. so, x = 100
Rosa : video games = 0.40(100) = 40
pizza 2/5 (100) = 200/5 = 40
total spending: 40 + 40 = 80
Robert : video games = 1/2 (100) = 50
pizza 0.25 (100) = 25
total spending: 50 + 25 = 75
Spending on video games
Rosa = 40
Robert = 50
Robert spent more of his allowance on video games than Rosa.
1/2 x > 0.4x
A = l x w
so you know that the length is 3m longer than the width, so you could use a formula to represent that
w = l + 3
you then substitute the second equation into the first to solve for l
70 = l x (l +3)
70 = l^2 + 3l
you could then rearrange the formula and solve for l using the quadratic formula
0 = l^2 + 3l - 70
l = -3 +- (square root (3)^2 - 4(1)(70)) / 2(1)
l = -3 +- (square root 9 + 280) / 2
l = -3 +- (square root 289) / 2
l = -3 +- 17 / 2
then you solve for the two seperate roots
l = -3 + 17 /2
l = 14 / 2
l = 7
or
l = -3 - 17 / 2
l = -20 / 2
l = -10
since a length cannot be negative, this root is not viable. therefore l = 7
to solve for w you would use
w = l + 3
w = 7 + 3
w = 10
hope this helps! if you did not understand a step or concept please let me know!
In reality your common denominator should be the Least Common Multiple. The LCM is the product of highest occurring primes of the numbers prime factorizations...
4=2*2, and 12=2*2*3. So the LCM is 2*2*3=12 Now that you know what the least common multiple is we can say that:
(3/4)(3/3)+5/12
9/12+5/12
(9+5)/12
14/12
7/6 which should be converted to a mixed number as this is an improper fraction...
(6+1)/6
1+1/6
1 1/6