39-Mavzu: Natural sonlarni ko’paytirish va uning xossalari Darsning maqsadi: Ta’limiy

Asosiy qism:

1-misol. Noma’lum qo’shiluvchini topish.

x+23=57 x=57-23 x=34

2-misol. Noma’lum kamayuvchini topish.

y-9=16 y=16+9 y=25

3-misol. Noma’lum ayriluvchini topish.

38-z=12 z=38-12 z=26

4-misol. (x+43)-23=52

x+43=52+23 x+43=75 x=75-43 x=32

149 – misol

To’g’ri to’rtburchak shaklidagi basseynning perimetri 80 m. Uning bo’yi enidan 10 m ortiq. Basseynning bo’yi va enini toping?

Yechish:

P= 2(a+b),

,

x= 15, 15 + 10 = 25 javob: 15 va 25

150 – misol

Tarozining bir pallasiga 5 kg li tosh qo’yildi, ikkinchi pallasiga esa olmalar qo’yildi. Tarozining olmali pallasiga 2 kg tosh qo’yilgach , u muvozanatga keldi. Olma necha kg ekan?

Yechish: 5 – 2 = 3 olma 3 kg ekan.

7-misol.

190+x=321 x=321-190 x=131

y+231=367 y=367-231 y=136

8-misol.

x+345=423 x=423-345 x=78

9-misol.

x+89=174 x=174-89 x=85

10-misol.

(x+74)+21=142 x+74=142-21 x+74=121 x=121-72 x=49

Mustahkamlash:

11-masala.

a) (x+24)-12=79 x+24=79+12 x+24=91 x=91-24 x=67

b) (y-29)+45=76 y-29=76-45 y-29=31 y=60

d) (122+x)-291=157 122+x=157+291 x=157+291-122 x=326

e) 784+(y-165)=869 y-165=869-784 y=869-784+165 y=250

f) (x+3013)+2222=7162 x+3013=7162-2222 x=7162-2222+3013 x=7953

g) 542-(y-307)=148 y-307=542-148 y-307=394 y=394+307 y=701

12-masala.

a) y+32=96 y=96-32 y=64

b) x+54=148 x=148-54 x=94
13-masala.

Ilhomda x dona

Botirda x+8 dona

Dilshodda x-3; jami: x+x+8+x-3=65 3x+5=65 3x=60 x=20

1-masala.

a) x+45=79 x=79-45 x=34 b) 1306+x=2176 x=2176-1306 x=1870

d) y-463=361 y=361+463 y=824 e) y-3072=1136 y=1136+3072 y=4208

f) 796-z=423 z=796-423 z=573 f) 2609-z=1423 z=2609-1423 z=1186