What is the % of return on investment formula ?

SIP calculator helps to leave aside the burden of lump sum investments and with smaller and more affordable investment on a regular basis. You can customize the amount and time as per your financial fit.
To calculate the SIP all you need is to input in the SIP calculator in the amount you want to invest, the no. of installments, the frequency of investments which is either monthly, quarterly and the expected rate of Return Resources and Information. This calculator helps you to figure out the regular investment amount to meet your financial goal.

https://www.mathsisfun.com/money/internal-rate-return.html
you have to guess what it is and I guess it to be 34.696 percent
From finance theory this is the finance formula
fv=pv(1+int)^n+pv2(1+int)^n2+pv3(1+int)^n3+pv4(1+int)^n4
10500=2000*(1.34696)^4+2500*(1.34696)^3+1500*(1.34696)^2+2000*(1.34696)^1
but I just used a spreadsheet and calculated the interest earned each year

So in cell c2 formula is =b2+(b2*$b$9/100) d2 you copy cell c2 to it and the interest rate will not alter its cell position
f6 formula is =sum(f1:f5)
then when you finish you just keep altering irr value to get 10500.

The reason for irr is to compare putting your money say in a bank account or in the government bonds market and comparing it to the IRR for your investment in question to see if it is worthwhile .
A true outlook would be to also factor in inflation over this time frame however the other investments are also affected by deflation so you are comparing like returns

From basic finance formula for future value which equals primary value multiplied by 1 plus the interest rate to the power of the number of terms
fv=pv(1+i)^t
3200=800x(1+i)^3
3200/800=(1+i)^3
4=(1+i)^3
4^-3=(1+i) >>> third square root on 4
1.5874105=1+i
.5874=i
in percentage this is 58.74 percent

Two ways to get to the same answer:
1) If X,Y, & Z are invested in the ratio of 4:5:6 then the amount invested in Z is 6/(4+5+6) times the total of N1200
= 6/15 * 1200
= N480
(Note: X is 4/15 and Y is 5/15 of the total investment,
4/15 + 5/15 + 6/15 = 15/15)
2) The second sentence says: Income from X plus income from Y minus income from Z is N140 and total income is N700. Total income is 700/1200 of the investment.
As formulas:
(Inc X + Inc Y) - Inc Z = 140 (rewriting: Inc X + Inc Y = 140 + Inc Z)
Inc X + Inc Y + Inc Z = 700
Substituting second formula into third:
(140 + Inc Z) + Inc Z = 700
140 + 2 Inc Z = 700
2Inc Z = 700 - 140 = 560
Inc Z = N280
Inc Z is also 700/1200 of investment in Z.
N280 = 700/1200 investment in Z
Investment in Z is 1200/700 * N280
Investment in Z is N480.

Following formula we can use.

S=P(1+RT)
WHERE S =INVEST AMOUNT+PROFIT
P=INVEST AMOUNT
R= RATE OF RETURN
T=TIME IN YEARS

EX : (300+x) = x(1+(5.4/100)*1)
(300+x)*100 = 105.4x
x=30000/5.4
x=5555. 4

A positive number is 5 times another number.If 21 is added to both the numbers,then one of the new numbers becomes twice the other number.What are the numbers