In this type of calculations, we decompose 13 by checking the lowest powers of the base, that is 40. for example we check 40^2, or 40^3 and compare it to 85
Notice
40*40*40=64,000
so we check how many time does 85 fit into 64,000:
64,000/85=752.94
85*753=64,005; 64000-64,005=-5
this means that

thus

Answer: 10 (mod85)
Remark, the set of all solutions is:
{......-75, 10, 95, .....}, that is 85k +10
Answer:
StartFraction StartRoot 3 EndRoot Over 3 EndFraction
Step-by-step explanation:
see the attached figure to better understand the problem
step 1
we know that
In the right triangle XYZ
---> adjacent side divided by the hypotenuse
substitute the values

Remember that

so
substitute



step 2
--> opposite side divided by the hypotenuse
substitute the values

Remember that

so


step 3
--> opposite side divided by adjacent side
substitute the values
Simplify

so
StartFraction StartRoot 3 EndRoot Over 3 EndFraction
Answer:
63.66
Step-by-step explanation:
Mean=(65.9+80.8+60.8+46.5+64.3)/5
Mean=63.66
810/2= 405
810/3= 270
810/4= 202.5 (not this one)
810/5= 162
810/6= 135
810/7= 115.71 ( not this one)
810/8= 101.25 (not this one)
810/9= 90
810/10= 81
810/11= 73.63 (not this one)
I hope this helps you!
(1) Repetition allowed : There are 4 choices for both positions, so 4 × 4 = 16 2-digit numbers can be formed. (2) Repetition not allowed : There are 4 options for tens position, and three options for ones position. Therefore, 4 × 3 = 12 2-digit numbers can be formed.