Question

The mean of 20 numbers is 40 . if 5 is subtracted from every number , what will be the new mean
1.45
2.40
3.20
4.35 ​

Answer 1

Answer:

2.40

Step-by-step explanation:

Answer 2

Gɪᴠᴇɴ :-

• The mean of 20 numbers is 40.

Tᴏ Fɪɴᴅ :-

• If 5 is subtracted from every number , what will be the new mean.

Sᴏʟᴜᴛɪᴏɴ :-

${\boxed{{\bf{</u><u>M</u><u>ean = \frac{</u><u>S</u><u>um \: of \: observations}{</u><u>N</u><u>umber \: of \: observations} }}}}$

$\sf\large</u><u>\</u><u>g</u><u>r</u><u>e</u><u>e</u><u>n</u><u>{</u><u>→</u><u> </u><u>4</u><u>0</u><u> = \frac{x}{</u><u>2</u><u>0</u><u>} }$

$\sf\large</u><u>\</u><u>g</u><u>r</u><u>e</u><u>e</u><u>n</u><u>{</u><u>→</u><u> </u><u>x = 20 \times 40 = 800}$

• Now,

$\sf\large\red{→ 5 \times 40 = 200}$

• Now ,200 is subtracted from 40.

$\sf\large\red{★ \:New \: mean = x - \frac{200}{40} }$

$\sf\large\red{→ \frac{800-200}{40} }$

$\sf\large\red{→ \frac{600}{40} }$

$\sf\large\red{→ 15 }$