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
#2 5.88 #3 6.510 #4 7.578 #5 9.835 #6 11.910 #7 3.72
Answer:

Step-by-step explanation:
we know that
If two figures are similar, then the ratio of its corresponding sides is proportional, and this ratio is called the scale factor
so

substitute the given value and solve for JK



Answer:
y = 112
Step-by-step explanation:
If y varies directly as the square of x
mathematically;
y ∝ x²
y = kx² where 'k' is the constant of proportionality
let u know the value of k for this equation by making k the subject of the formular from y = kx²
divide both sides by x²
k = y / x²
given that y = 567 x = 9
k = 567/(9)²
k = 567/81
k = 7
now to get the value of y when x = 4
from the equation conneting x, y,
y = kx²
y = 7 × (4)²
y = 7 × 16
y = 112