7 / 5 * 16 * 5 / 21 simple method / for fractional line

7 / 5 * 16 * 5 / 21 simple method / for fractional line

7/5*16*5/21
=（7X16X5）/（5X21）
=16X7/21X5/5
=16/3X1
=16/3
=5 and 1 / 3
This problem mainly uses the law of combination of multiplication for simple calculation

The simple method of (3 and 1 / 3 + 0.75-2 and 5 / 8) * 3

(3 1 / 3 + 0.75-2 5 / 8) * 3
=3*3+1/3*3+0.75*3-2.625*3
=9+1+2.25-7.875
=4.375
=4 and 3 / 8

A simple method is used to calculate: the second power of quarter * 6.12-the second power of 4 * 1.04

The second power of quarter * 6.12-4 * 1.04
=(1 * 6.12) & # 178; - (2 * 1.04) & # 178;
=3.06²-2.08²
=（3.06+2.08）（3.06-2.08）
=5.14*0.98
=5.14*(1-0.02)
=5.14- 0.1028
=5.0372

Simple method of 0.74 * 0.25 + 0.75

0.74*0.25+0.75
=0.25(0.74+3)
=0.25*3.74
=0.935

A simple method of 0.64 * 0.25 + 0.75 =

0.64*0.25+0.75
=0.16x4x0.25+0.75
=0.16+0.75
=0.91

A simple method of 4.75 + 3.59-0.59 + 4.25

4.75+4.25+【3.59—0.59】=12

A simple method for determination of 6.4 - (2.75 + 2.4) - 0.25

6.4-(2.75+2.4)-0.25
=6.4-2.75-2.4-0.25
=(6.4-2.4)-(2.75+0.25)
=4-3
=1

75 * 24 with a simple method

75×24
=75×(20+4)
=1500+300
=1800

Simple method 76 + 2.83 + 0.24

76+2.83+0.24
=76+3.07
=79.07.

3.6 divided by 1.2 + 3.6 divided by 2.4, how to use the simple method (note that divisor = sum of 2 divisors, 1.2 + 2.4 = 3.6 oh)

3.6 divided by 1.2 + 3.6 divided by 2.4
=(1.2+1.2+1.2)÷1.2+(1.2+1.2+1.2)÷1.2÷2
=1+1+1+(1+1+1)÷2
=3+1.5
=4.5