Question

Plz help me with this math and also explain

Answer 1

Step-by-step explanation:

[1]

• SI = $250
• Rate (R) = 12$\sf \dfrac{1}{2}$ %
• Time (t) = 4 years

$\longrightarrow \tt { SI = \dfrac{PRT}{100} }$

$\longrightarrow \tt { 250 = \dfrac{P \times 12\cfrac{1}{2} \times 4}{100} }$

$\longrightarrow \tt { 250 = \dfrac{P \times \cfrac{25}{2} \times 4}{100} }$

$\longrightarrow \tt { 250 = \dfrac{P \times 25 \times 2}{100} }$

$\longrightarrow \tt { 250 = \dfrac{P \times 50}{100} }$

$\longrightarrow \tt { 250 \times 100 = P \times 50}$

$\longrightarrow \tt { 25000 = P \times 50}$

$\longrightarrow \tt { \dfrac{25000}{50} = P }$

$\longrightarrow \underline{\boxed{ \green{ \tt { \ \; 500 = P }}}}$

Therefore principal is $500.

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[2]

• 2/7 of the balls are red.
• 3/5 of the balls are blue.
• Rest are yellow.
• Number of yellow balls = 36

Let the total number of balls be x.

→ Red balls + Blue balls + Yellow balls = Total number of balls

$\longrightarrow \tt{ \dfrac{2}{7}x + \dfrac{3}{5}x + 36 = x}$

$\longrightarrow \tt{ \dfrac{10x + 21x + 1260}{35} = x}$

$\longrightarrow \tt{ \dfrac{31x + 1260}{35} = x}$

$\longrightarrow \tt{ 31x + 1260= 35x}$

$\longrightarrow \tt{ 1260= 35x-31x}$

$\longrightarrow \tt{ 1260= 4x}$

$\longrightarrow \tt{ \dfrac{1260 }{4}= x}$

$\longrightarrow \underline{\boxed{ \tt { 315 = x }}}$

Total number of balls is 315.

A/Q,

3/5 of the balls are blue.

$\longrightarrow \tt{ Balls_{(Blue)} =\dfrac{3 }{5}x}$

$\longrightarrow \tt{ Balls_{(Blue)} =\dfrac{3 }{5}(315)}$

$\longrightarrow \tt{ Balls_{(Blue)} = 3(63)}$

$\longrightarrow \underline{\boxed{ \green {\tt { Balls_{(Blue)} = 189 }}}}$