2/5 in a decimal form= 0.4
2/5 in a percentage form= 40%
Hope this Helps!
Answer:
The correct option is;
C. 52.2 × 4.4 × 2 + 47.8 × 4.4 × 2
Step-by-step explanation:
The area of the square frame is the area of the inner square subtracted from the area of the outer square
Which gives;
52.2² - 47.8² = 440
Therefore;
Option A. 52.2² - 47.8² is a correct way of finding the area of the square frame
Option B. 2 × ((52.2×2.2) + (47.8×2.2)) = 440, is a correct way of finding the area of the square frame
Option C. 52.2 × 4.4 × 2 + 47.8 × 4.4 × 2 = 880, is not a correct way of finding the area of the square frame
The error is the thickness is 2.2 not 4.4
Option D. 100×(52.2 - 47.8) = (52.2 + 47.8) × (52.2 - 47.8) = 52.2² - 47.8² = 440, is a correct way of finding the area of the square frame
Answer:
99
Step-by-step explanation:
You can solve it by Squaring/multiply 18 by itself and 15 by itself then subtract them both:
(18 × 18) - (15 × 15)
324 - 225
99
You could also do difference of two squares:
(x² - y²)
= (x + y) (x - y)
= (18 + 15) (18 - 15)
= (33) (3)
= 99
Answer:
0.86
Step-by-step explanation:
You will get 0.85714.....
Then 0.86 is 2 dp