A two digit number can be written like AB or 10*A + B ( for example the number 36 can be written like 3*10 + 6 = 36)
You can write this problem as
10*A + B - (10*B + A) = 18
10*A + B - 10*B - A = 18
9*A - 9*B = 18
9(A - B) = 18
A - B = 2
A and B are digits, that means that both are either 0,1,2,3,4,5,6,7,8 or 9 (except that A cannot be 0 bcs the first digit in a two digit number cannot be 0)
So the combinations are
9 - 7 = 2
8 - 6 = 2
7 - 5 = 2
6 - 4 = 2
5 - 3 = 2
4 - 2 = 2
3 - 1 = 2
2 - 0 = 2
And we have the numbers:
97 ( B is 79)
86 ( B is 68)
75 ( B is 57)
64 ( B is 46)
53 ( B is 35)
42 ( B is 24)
31 ( B is 13)
20 ( B is 2)
Answer:
3.65102725271
Step-by-step explanation:
I think so but I'm not sure
Answer:
123 m²
Step-by-step explanation:
Surface area of the object = surface area of the bigger rectangular prism + (surface area of the smaller rectangular prism - area of the smaller rectangular prism base)
Surface area of the bigger rectangular prism:
L = 7 m
W = 3 m
H = 3 m
S.A = 2(LW + WH + LH)
S.A = 2(7*3 + 3*3 + 7*3)
S.A = 102 m²
Surface area of the smaller rectangular prism:
L = 3 m
W = 3 m
H = 1 m
S.A = 2(LW + WH + LH)
S.A = 2(3*3 + 3*1 + 3*1)
S.A = 30 m²
Area of the base of the smaller rectangular prism = L*W
L = 3 m
W = 3 m
Area = 3*3 = 9 m²
Surface area of the object = 102 + (30 - 9)
= 102 + 21
= 123 m²
Answer:
the first and second one
Step-by-step explanation:
the two last ones go over budget
1) 20×30=600 30×50=1500 total is 2100
2)50×30=1500 10×50= 500 total is 2000
3) 40×30=1200 40×50=2000 total is 3100>over budget.
4) 20×30=600 60×50=3000 total is 3600> way over budget.
