Question

now use the number line to find the missing factor. 0.7 times what number is 2.8? enter your answer.

0 0.7 1.4 2.1 2.8

0.7 × ? = 2.8

Explanation:

Step1: Recall the formula for missing factor

To find the missing factor in a multiplication equation \(a\times b = c\), we can use \(b=\frac{c}{a}\) (when \(a
eq0\)). Here, \(a = 0.7\), \(c = 2.8\), so we need to calculate \(\frac{2.8}{0.7}\).

Step2: Calculate the division

\(\frac{2.8}{0.7}=\frac{28}{7}\) (multiplying numerator and denominator by 10 to eliminate decimals). Since \(28\div7 = 4\), the missing factor is 4. We can also check with the number line: from 0, each step of 0.7 gets to 0.7 (1st step), 1.4 (2nd), 2.1 (3rd), 2.8 (4th step), so we need 4 steps, meaning the factor is 4.

Answer:

4