Let the unknown number be "n",
This number is sutracted from 46. So, 46 less n.
That is (46 - n).
The result to this is -21.
∴The equation would be;
46 - n = -21.
Now solve for n.
46-n=-21
46 + 21 =n
∴n=67
Answer: The unit rate is: " 1.5 patties / bun " ;
or, write as: "1.5 patties per bun" .
_____________________________________________________
The mistake is that the problem shown is incomplete.
The "unit rate" would be the "number of patterns per [single] bun."
_________________________________________________________
30 patties/ 20 buns = 3 pattern/ 2 buns;
= (3/2) patties/ bun = 1.5 patties / bun ;
or, write as: "1.5 patties per bun" .
__________________________________________________________
Leticia made a mistake in her step 2. She did subtraction before multiplication.
<h3 />
<h3>How to simplify an expression?</h3>
The expression can be simplified as follows;
4.5 ÷ 0.25 + 2.5 - 0.75 × 8
Hence, using Pemdas rule,
4.5 ÷ 0.25 + 2.5 - 0.75 × 8
18 + 2.5 - 0.75 × 8
18 + 2.5 - 6 = 14.5
Therefore, she made mistake in her step 2 because she was suppose to solve the multiplication before subtraction.
learn more on expression here: brainly.com/question/13545210
#SPJ1
