rumen

if we assume that there are no sales then the answer should be A). If there are sales the answer seems to be E)

since X= +/-1 then (a+b) can be odd or even, or when X= -1 (a+b)-even, when X=1 (a+b)-odd or even so seems that E) is the ans INMO

from 1) X^3 from B) X^30 X^3(X-1)>0 when X>1 and X combining both we get X

think that he means that we can have 7 or 22 points on the circle and thus we can not determine how many triangles we can make so B) makes sense

think that if you square both sides of the equation you will eliminate the absolute value sign, or x+15/3

why C) B is better for 1) if the area of Rec A is twice the area of B) then A has bigger perimeter

60minX(Ggpm-6)=120gal so you need 8 gpm

Pipe B can fill in one hour 1/40 of ther pool. Pipes A+B can fill 1/24 of the pool so they both can fill 8/120 if work for one hour. The time is 30 hours-15x1/40+15x1/24=120/120 or the pool is full.

think that it is C-1/0.833=1.2 which gives us 20%

total number of selecting 3 out of 10 peple is 120. You have 5 couples so in the 3 people team you will have one couple , which can be selected in 5 ways, and one more person , which can be chosen in 8 ways or 40 teams WITH married couples. The number of teams WITHOUT married couples is 120-40=80

Think the formula is ( n-1)n/2 or 7x8/2=28

For barley:grain think that barley is a sort of grain just as the pine is a sort of tree.Your choice vine:fruit makes no sense since vine is a plant not a fruit.

In order for the number to be even it should end with-0,2,4,6,8.When it ends with 0 we have 8x9=72 numbers, when it ends with 2, 7x9=63 numbers multiplied by 4 for the rest numbers 4,6,8 or 72+4x63=324 three-digit even numbers.Think that Zorrillo's approach is the best

Q1) 3^3x + 3^3x + 3^3x = 3^37 3^3x=27^x so 3*27^x=3*3^36 or 27^x=27^12 so X=12 Q2 Guess that the question is 4^(2x+2)=4^5 or 2x+2=5 so X=3/2

the remainder in your first problem is NOT 1 but 9. 9^231=81^115*9 which has 9 as unit's digit. Q2 7^231=2401^57*7^3 which has 3 as unit's digit, 2^28 has 6 or the product has 8 as unit's digit Q3 6^31 has 6, 7^7 has 3, 3^35 has 7 so the product has 6*3*7 or 6 as units digit