Answer:
108 cm²
Step-by-step explanation:
the surface area is the sum of all individual shapes areas on the surface.
2 right-angled triangles
3 rectangles
area of a right-angled triangle is At = a×b/2
At = 4×3/2 = 6 cm²
we need it twice : 12 cm²
one rectangle (length×width) = 8×3 = 24 cm²
one rectangle = 8×4 = 32 in²
one rectangle = 8×5 = 40 cm²
total surface area
A = 12+24+32+40 = 108 cm²
an area is always a square unit (power of 2).
a volume is always a cubic unit (power of 3).
and a length is always a simple unit (power of 1).
Answer:
5/21.
Step-by-step explanation:
Total number of balls = 7.
Prob(Blue on first pick) = 3/7
Prob(Blue on second pick) = 2/6 = 1/3
So Prob( 2 Blue's) = 3/7 * 1/3 = 3/21 = 1/7.
Prob(Red on first pick) = 2/7
Prob(Red on second pick) = 1/6
So Prob( 2 Red's) = 2/7 * 1/6 = 1/21.
Now the Probability of getting 2 white balls is the same as for the red balls
= 1/21.
Finally, the probability of 2 balls of the same colour
= 1/7 + 1/21 + 1/21
= 3/21 + 1/21 + 1/21
= 5/21.
1 in 28 chance that Patches will be selected
3 in 4 chance that a cat will be selected