60% of 20 quizzes = 60/100*20 quizzes = 12 quizzes
Amount of quizzes remaining = 50 quizzes - 20 quizzes = 30 quizzes
He passes 80% of those 30 quizzes, so
80/100 * 30 quizzes = 24 quizzes
So, he passed 12 quizzes from the initial bunch and 24 quizzes from the rest, which totals to 12 quizzes + 24 quizzes = 36 quizzes.
Then, you see that he passed 36 quizzes, out of the total 50 quizzes, so the ratio is 36 quizzes / 50 quizzes = 36/50, which when converted as a percentage is 36/50 * 100% = 72%.
Therefore, he passed 72% of the quizzes for the entire year.
Answer:
see explanation
Step-by-step explanation:
Using the trigonometric identity
sin²x + cos²x = 1
Consider the left side
2cos²A - 1 ← replace 1 by sin²A + cos²A
= 2cos²A - ( sin²A + cos²A)
= 2cos²A - sin²A - cos²A
= cos²A - sin²A = right side ⇒ verified
Answer:
lets just say the f stands for 1 and 1 times negative 4 is negative 4
and 5 will stay 5 the equation would be -4/5 so after u divide the 4 and the five you get negative 1
B. you have to be ready to multiply all the numbers to get your answer.
Answer:
14-2a
Step-by-step explanation:
Since 15 and 21 are not included: we will have
=15-2a-1
=14-2a