Question

9. A photograph of a bacteria enlarged 40,000 times attains a length of 6 cm as shown in the
diagram. What is the actual length of the bacteria? If the photograph is enlarged 10,000
times only, what would be its enlarged length?
خاک​

Answer 1

${\Large{\bold{\rm{\red{Required \; Solution}}}}} \; \; \; \; \ddag$

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.

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Hope this will help you....

Answer 2

Answer:

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.