15
63 x 5 = 315
315/20 = 15.75
hence, 15 $20 bills
Hello,
N is closed for an opération(µ) means that
a,b ∈ N : a µ b ∈N (i suppose so)
Answer (1) ex 2/3 ∉ N
Answer (4) ex 2-3 ∉ N
∀ a,b ∈ N: a+b ∈N is true ; not a answer.
∀ a,b ∈ N: a*b ∈N is true ; not a answer.
Answer:
3² + 6 × 2² - 4² ÷ 2³ = 31.
Step-by-step explanation:
0.625000 is the correct answer
What's a regular heptagon? "Hept-" means seven, so a "heptagon" is a seven-sided shape. A "regular" figure's sides are all the same length. So, each of the 7 sides are the same length.
Remember, perimeter is the sum of the lengths of all the sides in a polygon. We know one side measures three inches, so each of the others must also measure 3 inches. 3+3+3+3+3+3+3=3*7=21 inches.
Answer: 21 inches
