Addition and Subtraction of Decimal Fractions: Only addition and subtraction

First we will break down each of the factors in the exercise into a whole number and its remainder:

$8+0.5+5+0.2+8+0.4=$

Now we'll combine only the whole numbers:

$8+5+8=13+8=21$

Then we'll calculate the remainder:

$0.5+0.2+0.4=0.7+0.4=1.1$

Finally, we are left with the following:

$21+1.1=22.1$

According to the order of operations, we will solve the exercise from left to right.

We will first calculate the addition exercise in the vertical column, since it contains two numbers after the decimal point:

$0.85+7.61=8.46$

Now we will get the exercise:

$8.46+2.3=$

Let's remember that:

$2.3=2.30$

We will calculate in the vertical column and get:

$10.76$

The first step is factorising each of the terms in the exercise into a whole number and its remainder:

$10x+0.1x+5x+0.2x+2x+0.4x=$

Now we'll combine only the whole numbers:

$10x+5x+2x=15x+2x=17x$

Next, we will calculate the remainder:

$0.1x+0.2x+0.4x=0.3x+0.4x=0.7x$

Finally, we are left with the following:

$17x+0.7x=17.7x$

According to the order of operations rules, we'll solve the exercise from left to right:

$0.2x+8.6x=8.8x$

We'll break down 8.8 into a smaller addition exercise that will be easier for us to calculate:

$8x+0.8x+0.65x=$

Now we'll use the commutative property since the exercise only involves addition.

Let's focus on the leftmost addition exercise, remembering that:

$0.8=0.80$$$

We'll calculate the following exercise:

$0.80x+0.65x=1.45x$

And finally, we'll get the exercise:

$8x+1.45x=9.45x$