Hey there!!
Let us take the number as ' x '
20% of x
= (20/100) × ( x )
= ( 1/5 ) × ( x )
= x/5
The number is decreased by 20% of itself
x - x/5 = 56
5x - x / 5 = 56
4x/5 = 56
Multiplying by 5 on both sides
5x = 56 × 5
5x = 280
dividing by 5 on both sides
4x / 4 = 280 / 4
x = 70
The number is 70
Hope my answer helps!
Answer:
D
Step-by-step explanation:
multiple by
2*5= 10......
Oh, this is easy. For any prism, you find the surface area by finding the are of all the sides. I will post all surface area formulas here, for reference
Cube:
Surface area = 6 × a2
Right circular cylinder:
Surface area = 2 × pi × r2 + 2 × pi × r × h
pi = 3.14
h is the height
r is the radius
Rectangular prism:
Surface area = 2 × l × w + 2 × l × h + 2 × w × h
l is the length
w is the width
h is the height
Sphere:
Surface area = 4 × pi × r2
pi = 3.14
r is the radius
Right circular cone:
Surface area = pi × r2 + pi × r ×( √(h2 + r2))
pi = 3.14
r is the radius
h is the height
l is the slant height
Right square pyramid:
Surface area = s2 + 2 × s × l
s is the length of the base
h is the height
l is the slant height
Answer:
<h3>Therefore the sum if the series is 15.98!</h3>
The common ratio is 1/2 or 0.5 . If you multiply the current term by the the common ratio the the output will be the next term.
8⋅1/2=4
4⋅1/2=2
2⋅1/2=1 etc ...
because the absolute value of r is less than 1 we can use the following formula.
a/1−r where a is the first term and r is the common ratio
In our problem
a=8 and r=0.5
Substitute
8/1−0.5=8/0.5=16
The sum of this infinite geometric series is 16.
Also, another formula you can use that is guaranteed to work every time, no matter what, is:
Sn=a(r^n−1/r−1)
All the variables work the same way as above, and "n" is the number of terms in the series. So, say you wanted to find the sum of the first 10 terms and were to substitute everything in:
S10=8(0.5^10−1/0.5−1)
S10=15.984375
Therefore the sum if the series is 15.98!
Step-by-step explanation:
<h2>Hope it is helpful....</h2>
Distance from house to work (D) is 6km (A). House and school is 6cm on map 6cm=9km
so 4cm = (d)km
6....4
---X--- = (6 x d) 6d = (9 x 4) 36 so now
9....d
divide to get (d) 6d/6=36/6 so D=6
above are fractions sorry for the decimal points it wouldn't place the spaces without them.