How do you evaluate the expression: $28 \div 2 \div 2 \div 2$ $28 ÷ 2 ÷ 2 ÷ 2$ ?

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Answer 1 · 2016-07-17T10:19:30

$3 \frac{1}{2}$ $3 1/2$ by a variety of methods, but take care!

As there is only one operation (all division) we work from left to right.

$28 \div 2 \div 2 \div 2$ $28 div 2 div 2 div 2$

= $14 \div 2 \div 2$ $14 div 2 div 2$

= $7 \div 2$ $7 div 2$
= $3 \frac{1}{2}$ $3 1/2$

However, it is important to note that division is not commutative.

We also CANNOT do the following:

$28 \div 2 \div (2 \div 2)$ $28 div 2 div (2 div 2)$

This will give $14 \div 1 = 14$ $14 div 1 = 14$

Dividing by a divide should make a multiplication!

= $28 \div 2 \div (2 \times 2) = 14 \div 4 = 3 \frac{1}{2}$ $28 div 2 div (2xx2) = 14 div 4 = 3 1/2$

We CAN do the following:

$28 \div (2 \times 2 \times 2) = 28 \div 8 = 3 \frac{1}{2}$ $28 div(2xx2xx2) =28 div8 = 3 1/2$

We could also write the expression as a fraction:

$\frac{28}{2 \times 2 \times 2} = \frac{7}{2} = 3 \frac{1}{2}$ $28/(2 xx 2 xx 2) = 7/2 = 3 1/2$

How do you evaluate the expression: 28 ÷ 2 ÷ 2 ÷ 228÷2÷2÷228 ÷ 2 ÷ 2 ÷ 2?