Hey there! I'm happy to help!
Step 2 is incorrect. She added 4 and 2 first, but you are supposed to multiply and divide first. Then she multiplied 6 and 6, which is 36. Then she divided 36 and 2, which is 18, and then she subtracted 7, giving her 11. Step 2 is what threw the whole thing off.
Here is what Sandy should have done.
STEP 1: 6·4+2÷2-7
STEP 2: 24+1-7
STEP 3: 25-7
STEP 4: 18
I hope that this helps! Have a wonderful day! :D
That is the difference of two squares and is factored in this way:
(7 +x) * (7 -x)
Answer:
19 songs
Step-by-step explanation: 0.99 x 19 = 18.81
