Question

"Question 5 A photograph of a bacteria enlarged 50,000 times attains a length of 5 cm. What is the actual length of the bacteria? If the photograph is enlarged 20,000 times only, what would be its enlarged length?

Class 8 Direct and Inverse Proportions Page 208"

Answer 1

If two quantities increase or decrease together in such a manner that the ratio of their corresponding values remain constant, we say  that the two quantities vary  directly.

In other words x and y are said to vary directly if X/y = k , where k is a positive constant.

In direct Proportion
x/y= k

x=ky

So we can find value of k from known values, and then use the formula to calculate the unknown values.

When two quantities x and y are in direct proportion (or vary directly) they are also written as x∝y.
=========================================================

Solution:

[Table is in the attachment]

Let the actual length of bacteria be ‘x’ & enlarged length be y cm.

Here the number of times  the photograph of bacteria was enlarged  & the length of the bacteria are in direct proportion.

5/50000=x /1

X= 1/10000

x=0.0001cm 

 x=10^-4

Hence, the actual length of bacteria is 10^-4

 

Let the length of the bacteria when the photograph of bacteria was enlarged 20000 times be y

5/50000 = y/20000

y × 50000 = 5× 20000

y= 5× 20000/50000

y= 2cm.

Hence, the enlarged length of the bacteria is 2cm.

==========================================================

Hope this will help you....

Answer 2

Answer:

hey!

Step-by-step explanation:

hope this answer helps

love u