Question

IM IN A TEST NOW WILL AWARD BRAINLIEST!!!!!

Answer 1

The product has decreased by 80 %

Solution:

The product of the original numbers: xy

One number is decreased by 75 %

Let x be the number decreased by 75 %

new number = x - 75 % of x

$new\ number = x - 75 \% \times x\\\\new\ number = x(1-75 \%)\\\\new\ number = x(1-\frac{75}{100}) = x(1-0.75) = 0.25x$

Another number is decreased by 20 %

Let y be the number decreased by 20 %

new number = y - 20 % of y

$new\ number = y - 20 \% y\\\\new\ number = y(1-20 \%)\\\\new\ number = y(1-\frac{20}{100}) = y(1-0.2) = 0.8y$

Now the product is given as:

$product = 0.25x \times 0.8y = 0.2xy$

Now we have to find the percent decreased

Subtract new product and original product and then divide by original product . Multiply the result by 100 to get percentage

$percent\ decrease = \frac{0.2xy - xy}{xy} \times 100\\\\percent\ decrease = \frac{-0.8xy}{xy} \times 100 = -0.8 \times 100 = -80$

Here negative sign denotes decrease

Thus the product has decreased by 80 %