The correct question is
<span>Keiko sold 3 less than three-fourths of his sister’s sales. Which expression represents what Keiko sold?
Let
S----------------> </span><span>the amount that Keiko's Sister sold
</span>K----------------> the amount that Keiko sold
we know that
Keiko sold 3 less than three-fourths of his sister’s sales
K=(3/4)*S-3
the answer is
K=(3/4)*S-3
The explicit formula for this arithmetic sequence is A(n)=1/2•(-8)^(n-1)
To find the tip:
28 x 15/100 = 4.2 dollars
Add the tip to the cost of the lunch gives us the total cost:
28 + 4.2 = 32.2
For 100kg
15% : (100-x)0.15
75% : 0.75x
equation
(100-x)0.15 + 0.75x = 100*0.63
solve for x:
x = 80kg of 75%
20kg of 15%
