Question

There are three times as many girls as boys in a school . Find an expression , in terms of , for the total number of students in the school , where x represents the numbers of boys in the school .write this in algebraic expression.
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Answer 1

Here's what we know:

b = 3g (There are three times as many boys as girl)

b = g + 24 (there are 24 more boys than girls)

Since both equations equal b, they also equal one another:

3g = g + 24

Subtract g from both sides:

2g = 24

Divide both sides by 2:

g = 12

b = 3 * 12

b = 36

check:

36 = 12 + 24

36 = 36

p + d + h = 123 (peter + david + henry's weight is 123 kg)

p = d + 15 (peter is 15 kg heavier than David)

d = h - 3 (david is 3 kg lighter than henry)

Now that we have values for our variables, let's plug them in:

(d + 15) + (h - 3) + h = 123

(h - 3) + 15 + h - 3 + h = 123

Combine like terms:

3h + 9 = 123

Subtract 9 from both sides:

3h = 114

Divide by 3:

h = 38

d = 38 - 3

d = 35

p = 35 + 15

p = 50

check:

50 + 35 + 38 = 123

123 = 123