Before going into the details of the problem, let us first write down the most important information required for solving this problem.
1 ft = 12 inches
The distance that was crawled by Jack = 4 ft
= (4 * 12) inches
= 48 inches
The distance crawled by Christine = 3/4 of the distance crawled by Jack
= (3/4) * 48 inches
= 3 * 12 inches
= 36 inches
Then
The total distance crawled by the two children's = (48 + 36) inches
= 84 inches
So Jack and Christine together crawled a distance of 84 inches.
What is divide by-2 digit numbers well it's like (2x4)divided by what ever numbers.
1 2
2 4
0.49
x 3.5
______
245
1470
+_____
1.715
note : cross out the 2 & 4 on top of .49
5.25 pounds of one alloy containing 45% copper and 36.75 pounds of 69% copper is used to make 42 pounds of 66% copper
<h3>What is an
equation?</h3>
An equation is an expression that shows the relationship between two or more variables and numbers.
Let x represent the amount of 45% copper and y represent the amount of 66% copper needed to make 42 pounds of a third alloy containing 66% copper. Hence:
x + y = 42 (1)
Also:
0.45x + 0.69y = 42(0.66) (2)
This gives:
x = 5.25, y = 36.75
5.25 pounds of one alloy containing 45% copper and 36.75 pounds of 69% copper is used to make 42 pounds of 66% copper
Find out more on equation at: brainly.com/question/2972832
#SPJ1