29JUL21

While performing addition/subtraction on fractions, the key is “making the denominators equal”.

While performing addition/subtraction on decimal numbers, the key is “making the number of places equal”.

0.5+0.5=1

0.5–0.25=0.50–0.25=0.25

0.1–0.01=0.10–0.01=0.09

0.1+0.12+0.123=0.343

0.3–0.125=0.175

0.9+0.19+0.99=2.08

1.08–0.54=0.54

1.08–0.81–0.27=0

15.1–1.51–5.551=8.039

(17/10)–(87/100)

=1.7– 0.87=0.83

?–0.05 = 0.05

Answer: 0.1

3.5–? = 3.15

2 = 1+1

Adding 5 on both sides

2+5 = 1+1+5

Subtracting 2 from both sides

2 – 2 = 1 + 1 – 2

6 = 2+4

Dividing by 2 on both sides

6/2 = 2/2 + 4/2

7 = 3+4

Multiplying both sides by 5,

7*5 = 3*5 + 4*5

3.5–x = 3.15

Adding x on both sides,

3.5 – x + x = 3.15 + x

(The purpose of this is to make x positive.)

3.5 = 3.15 + x

3.15 + x = 3.5

(It is better to have x on the left side because it is the value of x which we are trying to find.)

Subtracting 3.15 from both sides

3.15 + x – 3.15 = 3.5 – 3.15

(The purpose of this is to remove 3.15 from the LHS so that only x remains in the LHS.)

x = 3.5 – 3.15

Therefore, x = 0.35