Simple calculation of 7.8 * 9.9 + 0.78

Simple calculation of 7.8 * 9.9 + 0.78

7.8*9.9+7.8*0.1
=7.8*(9.9+0.1)
=7.8*10
=78

How to calculate 9.81 + 9.82 + 9.83 + 9.84 + 9.85 simply?

=9.83×5
=49.15
Friends who ask questions by mobile phone can comment on [satisfaction] on the client
Help each other, wish common progress!

A sub branch's savings deposit was 30 million yuan last year. This year's fixed deposit increased by 25% and current deposit decreased by 25% compared with last year's, but the total deposit increased by 15%?

Suppose last year's fixed deposit is x million yuan and current deposit is y yuan. From the meaning of the question, x + y = 300025% X − 25% y = 3000 × 15%, we get x = 600y = 24002400 + 2400 × 25% = 30 million yuan and 600-600 × 25% = 4.5 million yuan. A: this year's fixed deposit is 30 million yuan and current deposit is 450 yuan,

According to 3000 divided by 25 minus 3000 divided by 30, make up a practical problem,

Each grade is divided into 3000 exercise books. There are 25 classes in grade one and 30 classes in grade two. How many more books are there in each class in grade one than in grade two?
3000 △ 25-3000 △ 30 = 120-100 = 20 copies