Two years ago, Mr Singh was 7 times as old as his son. In 3 years' time, he will be 4 times as old as his son. Find Mr Singh's present age.

37 years old.

Step-by-step explanation:

2 years ago

Singh-  7s

Son- s

3 years in the future(so 5 years forward)

Singh- 7s+5

Son- s+5

7s+5 = 4(s+5)

7s+5 = 4s+20

3s = 15

s=5

2 years ago the son was 5 so Mr. Singh was 35

Now Mr. Singh is 37

70,000 + 6,000 + 800 + 30

step-by-step explanation:

hello from mrbilldoesmath!

answer:

(7 x + 6 y) (49 x^2 - 42 x y + 36 y^2)

discussion:

the trick is to recognize that 343 = 7^3 and 216 = 6^3 and, in general,

a^3 + b^3 =   (a + b) (a^2 - a b + b^2).

in our case

343x^3+216y^3   =   (7x)^3 + (6y)^3

so take a = 7x and b = 6y in the above equation to get the answer.

you,

mrb