Read the situations given below. Write appropriate expressions for each of them and find their values. Class 7

Read the situations given below. Write appropriate expressions for each of them and find their values. Class 7

Question 1.

Read the situations given below. Write appropriate expressions for each of them and find their values. Class 7

(a) The district market in Begur operates on all seven days of a week. Rahim supplies 9 kg of mangoes each day from his orchard and Shyam supplies 11 kg of mangoes each day from his orchard to this market. Find the amount of mangoes supplied by them in a week to the local district market.

Solution:

Mango supplied each day = 9 kg + 11 kg

So, mango supplied in a week

= 7 × (9 + 11) kg .

= 7 × 20 kg = 140 kg.

(b) Binu earns ₹ 20,000 per month. She spends ₹ 5,000 on rent, ₹ 5,000 on food, and ₹ 2,000 on other expenses every month. What is the amount Binu will save by the end of a year?

Solution:

Amount save per month

= ₹ (20000 - 5000 - 5000 - 2000)

So, amount saved in a year

= ₹ 12 × (20000 - 5000 - 5000 - 2000)

= ₹ 12 × 8000 = ₹ 96000

(c) During the daytime a snail climbs 3 cm up a post, and during the night while asleep, accidentally slips down by 2 cm. The post is 10 cm high, and a delicious treat is on its top. In how many days will the snail get the treat?

Solution:

Actual height climb by the snail in a day

= 3 cm - 2 cm = 1 cm

In 7 days, it will be able to climb 7 × 1 = 7 cm. On 8th day, snail will reach at the top of the post, because 7 cm + 3 cm = 10 cm and he will not slip as the time of reach up at top will be day time.

So, he will get the treat in 8 days.

Question 2.

Melvin reads a two-page story every day except on Tuesdays and Saturdays. How many stories would he complete reading in 8 weeks? Which of the expressions below describes this scenario? Class 7

(a) 5 × 2 × 8

(b) (7 - 2) × 8

(c) 8 × 7

(d) 7 × 2 × 8

(e) 7 × 5 - 2

(f) (7 + 2) × 8

(g) 7 × 8 - 2 × 8

(h) (7 - 5) × 8

Solution:

He will complete reading (7 - 2) × 8 stories i.e., 40 stories.

Thus, expression given at (b) above describe this scenario.