Answer :
x = 53.85
Step by step explanation:
If 78% of x (some numbers) is equal to 42, then we must set this as an equation to find it.
1) Rewriting 78% as a fraction and considering that when we say 78% of some number (x) we mean a product.
78% = 78/100 ➡️ 78/100x = 42
2) Then we can go on :
100 * 78/100x = 42 * 100
78x = 4200
78x/78 = 4200/78 ➡️ x = 53.85
3) Alternatively, simply dividing 42 by 0.78 (78%) would come to the same result :
42/0.78 = 53.85
Step-by-step explanation:
given a normal distribution with the given parameters the probability (= the % of the area of the distribution curve) for a number to be between 203 and 1803 is
0.9987
so, 99.87% of all numbers are expected to be in that range.
for 350,000 numbers that means
350,000×0.9987 = 349,545 numbers are expected to be between 203 and 1803.
Right square pyramid V=189cm³
