The sixth grade math problem of Sandao primary school The area of an aquatic plant covering the surface of a lake doubles every day. It covers the whole lake in 16 days. After 14 days, what percentage of the whole lake is covered? There are two stores. If the profit of store a increases by 20% and that of store b decreases by 10%, the profits of these two stores are the same. The profit of store a is ()% of that of store B There is a cylinder whose bottom area is equal to the side area. If the bottom area of the cylinder remains unchanged and its height is increased by 3 cm, its surface area will be increased by 1130.4 square cm

The sixth grade math problem of Sandao primary school The area of an aquatic plant covering the surface of a lake doubles every day. It covers the whole lake in 16 days. After 14 days, what percentage of the whole lake is covered? There are two stores. If the profit of store a increases by 20% and that of store b decreases by 10%, the profits of these two stores are the same. The profit of store a is ()% of that of store B There is a cylinder whose bottom area is equal to the side area. If the bottom area of the cylinder remains unchanged and its height is increased by 3 cm, its surface area will be increased by 1130.4 square cm

The area of an aquatic plant covering the surface of a lake doubles every day. It covers the whole lake in 16 days. After 14 days, what percentage of the whole lake is covered?
The area covered by one kind of aquatic plant is doubled every day
It's 1 / 2 in 15 days
It's a quarter in 14 days
There are two stores. If the profit of store a increases by 20% and that of store b decreases by 10%, the profits of these two stores are the same. The profit of store a is (75)% of that of store B
(1-10%)÷(1+20%)=75%
There is a cylinder whose bottom area is equal to the side area. If the bottom area of the cylinder remains unchanged and its height is increased by 3 cm, its surface area will be increased by 1130.4 square cm
The surface perimeter of the cylinder can be obtained as follows:
1130.4 △ 3 = 376.8 (CM)
The radius obtained is as follows:
376.8 ÷ (2x3.14) = 60 (CM)
The original surface area is as follows:
60x60x3.14x(2+1)
=1130.4x3
=3391.2 (cm2)