Let us determine the product of 438 and 17 by partial products.
Consider
and
So,
=
= 7446
Therefore, the product of 438 and 17 is 7446.
No, Sandra's answer is not correct.
Because she should have expressed 17 as (10+7), then if she multiplied (438 by 10) and (438 by 7). And, then added the results.Then her answer would be correct.
Answer:
Andrew walks more steps than Sarah.
Step-by-step explanation:
The question is incomplete. The complete question is :
Andrew and Sarah are tracking the number of steps they walk. Andrew records that he can walk 6000 steps in 50 minutes. Sarah writes the equation y=118x, where y is the number of steps and x is the number of minutes she walks, to describe her step rate. This week, Andrew and Sarah each walk for a total of 5 hours. Who walks more steps?
Solution:
Given:
Andrew walks 6000 steps in 50 minutes.
Number of steps Sarah walks is given by the equation :
where is the number of steps and
is the number of minutes she walks.
Finding the number of steps each walks in 5 hours.
Total number of minutes in 5 hours =
For Andrew:
Using unitary method:
If in 50 minutes Andrew walks = 6000 steps.
In 1 minute he will walk = = 120 steps
In 300 minutes he will walk = steps
Thus, Andrew will walk 36,000 steps in 5 hours.
For Sarah:
We will plugin in the equation and solve for
.
We have:
∴
Thus, Sarah will walk 35,400 steps in 5 hours.
Therefore, Andrew walks more steps than Sarah as .