A and B have certain number of mangoes. A says to B, " If you give me 10 of your mangoes, I will have twice as many as left with you." B replies, "If you give me 10 of your mangoes, I will have thrice the number of mangoes left with you. Find the original number of mangoes each had.

A had 22 mangoes, B had 26 mangoes

Step-by-step explanation:

We can write the following system:

A + 10 = 2(B - 10) -- Equation 1

3(A - 10) = B + 10 -- Equation 2

A + 10 = 2B - 20 → A = 2B - 30 -- Equation 3 (Simplify Equation 1)

3(2B - 30 - 10) = B + 10 -- Equation 4 (Substitute 3 into 2)

3(2B - 40) = B + 10

6B - 120 = B + 10

5B = 130

B = 26 -- (Solve for B in Equation 4)

A = 2 * 26 - 30 = 22 -- (Substitute B = 26 into Equation 3)

answer: okw

step-by-step explanation:

d. 24+-0.114

step-by-step explanation:

the question requires us to calculate the approximate 95% confidence interval for the mean number of ounces of ketchup per bottle in the sample given the following statistics;

sample mean = 24

standard deviation, σ = 0.4

sample size , n = 49

the confidence interval for a population mean is calculated using the formula;

sample mean ± z-score*(σ/sqrt(n))

the z-score associated with a 95% confidence interval, from the standard normal tables, is;

1.96

substituting these values into the formula;

24 ± 1.96*(0.4/7)

= 24 ± 0.112

from the alternatives given, choice d is closest to the above expression;